Week 15: Installation of Basic Software

Installation of Basic Software 

This lesson actual we will deal in with installation of Microsoft windows 7 and Microsoft Office 2007. the following videos will show step by step of installing these two packages.

Installing windows operating system

Installing office package

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week 9 - 11: Word processor

Introduction to Microsoft word

Introduction to Microsoft Word 2007

This lesson is a quick introduction to Microsoft Word 2007. After finishing this lesson please review the Creating Accessible Word documents and Excel Workbooks SoftChalk lesson.

Starting Word 2007

• Select Start
• Select All Programs
• Select Microsoft Office
• Select Microsoft Office Word 2007

Or search for winword.exe.

Parts of the Word 2007 Screen

Word starts and a new document window opens. You are now ready to begin creating a new document or editing an existing one. Think of this window as a clean sheet of paper with margins and spacing already set. For this discussion we will need to change the View to Print Layout with Ruler (click on View tab, choose Print Layout in the Document Views section of the Ribbon then select Ruler from the Show/Hidesection).

For full course of Microsoft word 2007 please click the link bellow:

Microsoft word 2007 lectures.

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Week 12 - 14: Spread sheets

Spread sheets

INTRODUCTION OF MICROSOFT EXCEL

Microsoft Excel is an electronic spreadsheet. You can use it to organize your data into rows and columns. You can also use it to perform mathematical calculations quickly. This tutorial teaches Microsoft Excel basics. Although knowledge of how to navigate in a Windows environment is helpful, this tutorial was created for the computer novice.

Excel environment

Since we will be using Excel for statistical analysis, we provide a brief overview of the Excel environment with particular emphasis on the latest versions of Excel (Excel 2007, Excel 2010, Excel 2013 and Excel 2016) and the capabilities most useful for statistical analysis. Together with Excel’s online help facilities (accessible by pressing in Excel the F1 function key), this will provide you with sufficient background to carry out the analyses described in the remainder of this website.

Working with workbook and worksheet

Microsoft Excel consists of worksheets. Each worksheet contains columns and rows. The columns are lettered A to Z and then continuing with AA, AB, AC and so on; the rows are numbered 1 to 1,048,576. The number of columns and rows you can have in a worksheet is limited by your computer memory and your system resources.
The combination of a column coordinate and a row coordinate make up a cell address. For example, the cell located in the upper-left corner of the worksheet is cell A1, meaning column A, and row 1. Cell E10 is located under column E on row 10. You enter your data into the cells on the worksheet

Entering data (text, Number)

You have several options when you want to enter data manually in Excel. You can enter data in one cell, in several cells at the same time, or on more than one worksheet at once. The data that you enter can be numbers, text, dates, or times. You can format the data in a variety of ways. And, there are several settings that you can adjust to make data entry easier for you

Formatting (Font,number) and customizing data

Cell formatting The icons on the Home ribbon provide you with a variety of formatting options. To apply any of these, just select the cell or cells that you want to format, and then click the desired icon. Commonly used formatting attributes include: Font and size Bold, Italic, Underline Cell borders Background and Font color Alignment: Left, Centre or Right Merge text across multiple cells Wrap text within a cell Rotate angle of text Format number as Currency, Percentage or Decimal Increase or Decrease number of decimal places The Format Painter allows you to copy formatting attributes from one cell to a range of cells.

Editing spreadsheets

Enter the data

1. Click a cell, and then type data in that cell.
2. Press ENTER or TAB to move to the next cell.
Tip To enter data on a new line in a cell, enter a line break by pressing ALT+ENTER.
3. To enter a series of data, such as days, months, or progressive numbers, type the starting value in a cell, and then in the next cell type a value to establish a pattern.
For example, if you want the series 1, 2, 3, 4, 5..., type 1 and 2 in the first two cells.
Select the cells that contain the starting values, and then drag the fill handle across the range that you want to fill.
Tip To fill in increasing order, drag down or to the right. To fill in decreasing order, drag up or to the left.

Formulas and function

Creating / copying formulas

Microsoft Excel provide a really quick way to copy a formula down a column. You just do the following:

Enter a formula in the top cell.

Select the cell with the formula, and hover the mouse cursor over a small square at the lower right-hand corner of the cell, which is called the Fill handle. As you do this, the cursor will change to a thick black cross.
Hold and drag the fill handle down the column over the cells where you want to copy the formula.

Cell referencing

Excel is dynamic when it comes to cell addresses. If you have a cell with a formula that references a different cell’s address and you copy the formula from the first cell to another cell, Excel updates the cell reference inside the formula. Try an example:
1. In cell B2, enter 100.
2. In cell C2, enter =B2*2.
3 . Press Enter.
4. Cell C2 now returns the value 200.
5. If C2 is not the active cell, click it once.
6. Press Ctrl+C, or click the Copy button on the Home tab.
7. Click cell C3.
8. Press Ctrl+V, or click the Paste button on the Home tab

Using insert function button

1. Select the cell into which you want to enter the formula.
2. Select the Insert Function button in the Formula Bar
3. Enter a description of what you want to do and press [Return].
4. Select the desired function in the Select a function list.
5. Select OK.
6. Click the Collapse Dialog button at the right of the first argument edit box.
7. Select the range you want to use in the calculation.
8. Release the mouse button.
9. Click the Expand Dialog button.
10. Repeat steps 6 to 9 for any additional arguments you need to select.
10. Select OK

Using nested functions

A nested function uses a function as one of the arguments. Excel allows you to nest up to 64 levels of functions. Users typically create nested functions as part of a conditional formula. For example, IF(AVERAGE(B2:B10)>100,SUM(C2:G10),0). The AVERAGE and SUM functions are nested within the IF function. The structure of the IF function is IF(condition test, if true, if false). You can use the AND, OR, NOT, and IF functions to create conditional formulas. When you create a nested formula, it can be difficult to understand how Excel performs the calculations. You can use the Evaluate Formula dialog box to help you evaluate parts of a nested formula one step at a time

Using SUM/COUNT/MIN/AVERAGE/RANK

• example of sum

• example of min

• example of average 

• example of Rank

• if statement and nested if

Working with charts

A chart is a tool you can use in Excel to communicate data graphically. Charts allow your audience to see the meaning behind the numbers, and they make showing comparisons andtrends much easier. In this lesson, you'll learn how to insert charts and modify them so they communicate information effectively.

Sorting and querying data

This example teaches you how to import data from a Microsoft Access database by using the Microsoft Query Wizard. With Microsoft Query, you can select the columns of data that you want and import only that data into Excel.

1. On the Data tab, click From Other Sources, From Microsoft Query.

The 'Choose Data Source" dialog box appears.
2. Select MS Access Database* and check 'Use the Query Wizard to create/edit queries'.
3. Click OK.
4. Select the database and click OK.
This Access database consists of multiple tables. You can select the table and columns you want to include in your query.
5. Select Customers and click the > symbol.
6. Click Next.
To only import a specified set of records, filter the data. 7. Click City from the 'Column to filter' list and only include rows where City equals New York
8. Click Next.
You can sort your data if you want (we don't do it here).
9. Click Next.
10. Click Finish to return the data to Microsoft Excel.
11. Select how you want to view this data, where you want to put it, and click OK.
Result:
Note: when your Access data changes, you can click Refresh to update the data in Excel.

Freeze pane Select the View tab from the toolbar at the top of the screen and click on the Freeze Panes button in the Window group. Then click on the Freeze Top Row option in the popup menu.

Data validation 

Linking worksheets:

Importing and Exporting data

export to word The simplest way to display Excel data in a Word document is to use Copy/Paste

Open the destination Word document.
In the source Excel spreadsheet, select the data you want to copy then hit CTRL-C.
In the destination Word document, place the cursor where you want the data, then hit CTRL-V.

The default paste will use the Keep Source Formatting (A) paste option. This preserves any formatting you have done in Excel and pastes the data into Word as a table using that same formatting. As you can see, you may need to clean up your table after the paste to make it look correct in the new document.
To change the paste option, click the Ctrl dropdown option in the bottom right corner of your new table after pasting and select a new option. Other Paste options include: Use Destination Styles (B) – This will paste the data into Word as a table and adapt the display elements into the same formatting as the Word document. Use this to make your fonts and colors consistent in the destination without having to edit in Excel beforehand.

Copy as Picture (C) – This will paste the data range as a Word image object. You will be able to resize and edit the image as you would any other picture, but you will not be able to edit the data. The paste will use the original Excel formatting to generate the picture.

Import a word table

Open a new or existing document in Microsoft Word.

Click the "Insert" tab > Locate the "Tables" group.

Select the "Table" icon > Choose the "Insert Table..." option.

Set the "Number of columns," "Number of rows," and "AutoFit behavior" to your desired specifications > Click [OK].

Open the Excel file and use your mouse to select the data you wish to import.
Right-click on the range of cells you have highlighted and select "Copy."
Switch back to Word and highlight the table cells where you want to import the Excel data.
Right-click on the Word table and click the option you want under "Paste Options."


Import a text fileThere are two ways to import data from a text file by using Microsoft Excel: You can open the text file in Excel, or you can import the text file as an external data range. To export data from Excel to a text file, use the Save As command.
There are two commonly used text file formats:

Delimited text files (.txt), in which the TAB character (ASCII character code 009) typically separates each field of text.
Comma separated values text files (.csv), in which the comma character (,) typically separates each field of text.You can change the separator character that is used in both delimited and .csv text files. This may be necessary to make sure that the import or export operation works the way that you want it to.
Notes: You can import or export up to 1,048,576 rows and 16,384 columns.

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Week 7 - 8: Internet and world wide web

Internet and world wide web

Internet

The Internet is the global system of interconnected computer networks that use the Internet protocol suite (TCP/IP) to link devices worldwide. It is a network of networks that consists of private, public, academic, business, and government networks of local to global scope, linked by a broad array of electronic, wireless, and optical networking technologies. The Internet carries an extensive range of information resources and services, such as the inter-linked hypertext documents and applications of the World Wide Web (WWW),electronic mail, telephony, and peer-to-peer networks for file sharing. 

The origins of the Internet date back to research commissioned by the United States federal government in the 1960s to build robust, fault-tolerant communication via computer networks. The primary precursor network, the ARPANET, initially served as a backbone for interconnection of regional academic and military networks in the 1980s. The funding of the National Science Foundation Networkas a new backbone in the 1980s, as well as private funding for other commercial extensions, led to worldwide participation in the development of new networking technologies, and the merger of many networks. The linking of commercial networks and enterprises by the early 1990s marks the beginning of the transition to the modern Internet, and generated a sustained exponential growth as generations of institutional, personal, and mobile computers were connected to the network. Although the Internet was widely used by academia since the 1980s, the commercialization incorporated its services and technologies into virtually every aspect of modern life.

Internet use grew rapidly in the West from the mid-1990s and from the late 1990s in the developing world. In the 20 years since 1995, Internet use has grown 100-times, measured for the period of one year, to over one third of the world population. Most traditional communications media, including telephony, radio, television, paper mail and newspapers are being reshaped or redefined by the Internet, giving birth to new services such as email, Internet telephony, Internet television music, digital newspapers, and video streaming websites. Newspaper, book, and other print publishing are adapting to website technology, or are reshaped into blogging,web feeds and online news aggregates. The entertainment industry was initially the fastest growing segment on the Internet.[citation needed] The Internet has enabled and accelerated new forms of personal interactions through instant messaging,Internet forums, and social networking. Online shopping has grown exponentially both for major retailers and small businesses and entrepreneurs, as it enables firms to extend their "bricks and mortar" presence to serve a larger market or even sell goods and services entirely online. Business-to-business and financial services on the Internet affect supply chains across entire industries.

The Internet has no centralized governance in either technological implementation or policies for access and usage; each constituent network sets its own policies.[7] Only the over reaching definitions of the two principal name spaces in the Internet, the Internet Protocol address space and the Domain Name System (DNS), are directed by a maintainer organization, the Internet Corporation for Assigned Names and Numbers (ICANN). The technical underpinning and standardization of the core protocols is an activity of the Internet Engineering Task Force (IETF), a non-profit organization of loosely affiliated international participants that anyone may associate with by contributing technical expertise.

Web browser

A web browser (commonly referred to as a browser) is a software application for retrieving, presenting and traversing information resources on the World Wide Web. An information resource is identified by a Uniform Resource Identifier (URI/URL) that may be a web page, image, video or other piece of content. Hyperlinks present in resources enable users easily to navigate their browsers to related resources. Although browsers are primarily intended to use the World Wide Web, they can also be used to access information provided by web servers in private networks or files in file systems. The major web browsers are Firefox, Google Chrome, Internet Explorer/Microsoft Edge, Opera, and Safari

Internet Explorer

Internet Explorer (formerly Microsoft Internet Explorer and Windows Internet Explorer, commonly abbreviated IEor MSIE) is a discontinued series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems, starting in 1995. It was first released as part of the add-on package Plus! for Windows 95that year. Later versions were available as free downloads, or in service packs, and included in the original equipment manufacturer (OEM) service releases of Windows 95 and later versions of Windows.

Internet Explorer was one of the most widely used web browsers, attaining a peak of about 95% usage share during 2002 and 2003. This came after Microsoft used bundling to win the first browser war against Netscape, which was the dominant browser in the 1990s. Its usage share has since declined with the launch of Firefox (2004) and Google Chrome (2008), and with the growing popularity of operating systems such as macOS, Linux, iOS and Android that do not run Internet Explorer. Estimates for Internet Explorer's overall market share range from 5.45% to 27.38% or by Stat Counter's numbers ranked 3rd, just after Firefox (or even as low as 6th when counting all platforms, after Opera (and behind Safari), as of August 2016(browser market share is notoriously difficult to calculate). Microsoft spent over US$100 million per year on Internet Explorer in the late 1990s, with over 1,000 people working on it by 1999.

Versions of Internet Explorer for other operating systems have also been produced, including Internet Explorer for Mac andInternet Explorer for UNIX (Solaris and HP-UX), an Xbox 360 version called Internet Explorer for Xbox and an embedded OEM version called Pocket Internet Explorer, later rebranded Internet Explorer Mobile made for Windows Phone, Windows CE, and previously, based on Internet Explorer 7 for Windows Mobile.

On March 17, 2015, Microsoft announced that Microsoft Edge will replace Internet Explorer as the default browser on its Windows 10 devices. This effectively makes Internet Explorer 11 the last release. Internet Explorer will, however, remain on some versions of Windows 10 primarily for enterprise purposes. Starting January 12, 2016, only Internet Explorer 11 is supported

The browser has been scrutinized throughout its development for use of third-party technology (such as the source code of Spyglass Mosaic, used without royalty in early versions) and security and privacy vulnerabilities, and the United States and the European Union have alleged that integration of Internet Explorer with Windows has been to the detriment of fair browser competition with more security than older versions, according to Microsoft. Support varies based on the operating system's technical capabilities and its support life cycle.

Internet address

IP address

An Internet Protocol address (IP address) is a numerical label assigned to each device (e.g., computer, printer) participating in a computer network that uses the Internet Protocol for communication. An IP address serves two principal functions: host or network interface identification and location addressing. Its role has been characterized as follows: "A name indicates what we seek. An address indicates where it is. A route indicates how to get there." The designers of the Internet Protocol defined an IP address as a 32-bit number and this system, known as Internet Protocol Version 4 (IPv4), is still in use today. However, because of the growth of the Internet and the predicted depletion of available addresses, a new version of IP (IPv6), using 128 bits for the address, was developed in 1995.[3] IPv6 was standardized as RFC 2460 in 1998,[4] and its deployment has been ongoing since the mid-2000s. IP addresses are usually written and displayed in human-readable notations, such as 172.16.254.1 (IPv4), and 2001:db8:0:1234:0:567:8:1 (IPv6). The Internet Assigned Numbers Authority (IANA) manages the IP address space allocations globally and delegates five regional Internet registries (RIRs) to allocate IP address blocks to local Internet registries (Internet service providers) and other entities.

IP versions

Two versions of the Internet Protocol (IP) are in use: IP Version 4 and IP Version 6. Each version defines an IP address differently. Because of its prevalence, the generic term IP address typically still refers to the addresses defined by IPv4. The gap in version sequence between IPv4 and IPv6 resulted from the assignment of number 5 to the experimentalInternet Stream Protocol in 1979, which however was never referredto as IPv5.

Subnetting

In the early stages of development of the Internet Protocol, network administrators interpreted an IP address in two parts: network number portion and host number portion. The highest order octet (most significant eight bits) in an address was designated as the network number and the remaining bits were called the rest field or host identifier and were used for host numbering within a network. 

This early method soon proved inadequate as additional networks developed that were independent of the existing networks already designated by a network number. In 1981, the Internet addressing specification was revised with the introduction of classful network architecture.

Classful network design allowed for a larger number of individual network assignments and fine-grained subnetwork design. The first three bits of the most significant octet of an IP address were defined as the class of the address. Three classes (A, B, and C) were defined for universal unicast addressing. Depending on the class derived, the network identification was based on octet boundary segments of the entire address. Each class used successively additional octets in the network identifier, thus reducing the possible number of hosts in the higher order classes (B and C). The following table gives an overview of this now obsolete system.

Historical classful network architecture
Class	Leading bits	Size of network number bit field	Size of rest bit field	Number of networks	Addresses per network	Start address	End address
A	0	8	24	128 (27)	16,777,216 (224)	0.0.0.0	127.255.255.255
B	10	16	16	16,384 (214)	65,536 (216)	128.0.0.0	191.255.255.255
C	110	24	8	2,097,152 (221)	256 (28)	192.0.0.0	223.255.255.255

Classful network design served its purpose in the startup stage of the Internet, but it lacked scalability in the face of the rapid expansion of the network in the 1990s. The class system of the address space was replaced with Classless Inter-Domain Routing (CIDR) in 1993. CIDR is based on variable-length subnet masking (VLSM) to allow allocation and routing based on arbitrary-length prefixes.

Today,remnants of classful network concepts function only in a limited scope as thedefault configuration parameters of some network software and hardwarecomponents (e.g. netmask), and in the technical jargon used in network administrators'discussions.

Private addresses

Early network design, when global end-to-end connectivity was envisioned for communications with all Internet hosts, intended that IP addresses be uniquely assigned to a particular computer or device. However, it was found that this was not always necessary as private networks developed and public address space needed to be conserved.

Computers not connected to the Internet, such as factory machines that communicate only with each other via TCP/IP, need not have globally unique IP addresses. Three non-overlapping ranges of IPv4 addresses for private networks were reserved in RFC 1918. These addresses are not routed on the Internet and thus their use need not be coordinated with an IP address registry.

Today, when needed, such private networks typically connect to the Internet through network address translation (NAT).

IANA-reserved private IPv4 network ranges
	Start	End	No. of addresses
24-bit block (/8 prefix, 1 × A)	10.0.0.0	10.255.255.255	16777216
20-bit block (/12 prefix, 16 × B)	172.16.0.0	172.31.255.255	1048576
16-bit block (/16 prefix, 256 × C)	192.168.0.0	192.168.255.255	65536

Any user may use any of the reserved blocks. Typically, a network administrator will divide a block into subnets; for example, many home routers automatically use a default address range of 192.168.0.0 through 192.168.0.255 (192.168.0.0/24).

IPv4 address exhaustion

Highlevels of demand have decreased the supply of unallocated Internet Protocol Version 4 (IPv4) addresses available for assignmentto Internet service providers and end user organizations since the 1980s.This development is referred to as IPv4 address exhaustion. IANA's primary addresspool wasexhausted on 3 February 2011, when the last five blocks were allocated to thefive RIRs. APNIC was the first RIR to exhaust its regionalpool on 15 April 2011, except for a small amount of address space reserved forthe transition to IPv6, intended to be allocated in a restricted process.

IPv6 addresses 

The rapid exhaustion of IPv4 address space prompted the Internet Engineering Task Force (IETF) to explore new technologies to expand the addressing capability in the Internet. The permanent solution was deemed to be a redesign of the Internet Protocol itself. This new generation of the Internet Protocol was eventually named Internet Protocol Version 6 (IPv6) in 1995. The address size was increased from 32 to 128 bits (16 octets), thus providing up to 2¹²⁸ (approximately3.403×10³⁸) addresses. This is deemed sufficient for the foreseeable future.

The intent of the new design was not to provide just a sufficient quantity of addresses, but also redesign routing in the Internet by more efficient aggregation of subnetwork routing prefixes. This resulted in slower growth of routing tables in routers. The smallest possible individual allocation is a subnet for 2⁶⁴ hosts, which is the square of the size of the entire IPv4 Internet. At these levels, actual address utilization rates will be small on any IPv6 network segment. The new design also provides the opportunity to separate the addressing infrastructure of a network segment, i.e. the local administration of the segment's available space, from the addressing prefix used to route traffic to and from external networks. IPv6 has facilities that automatically change the routing prefix of entire networks, should the global connectivity or the routing policy change, without requiring internal redesign or manual renumbering.

The large number of IPv6 addresses allows large blocks to be assigned for specific purposes and, where appropriate, to be aggregated for efficient routing. With a large address space, there is no need to have complex address conservation methods as used in CIDR.

All modern desktop and enterprise server operating systems include native support for the IPv6 protocol, but it is not yet widely deployed in other devices, such as residential networking routers, voice over IP (VoIP) and multimedia equipment, and network peripherals.

Private addresses

Just as IPv4 reserves addresses for private networks, blocks of addresses are set aside in IPv6. In IPv6, these are referred to as unique local addresses (ULA). RFC 4193reserves the routing prefix fc00::/7 for this block which is divided into two /8 blocks with different implied policies. The addresses include a 40-bit pseudorandom number that minimizes the risk of address collisions if sites merge or packets are misrouted.

Early practices used a different block for this purpose (fec0::), dubbed site-local addresses. However, the definition of what constituted sites remained unclear and the poorly defined addressing policy created ambiguities for routing. This address type was abandoned and must not be used in new systems.

Addresses starting with fe80:, called link-local addresses, are assigned to interfaces for communication on the attached link. The addresses are automatically generated by the operating system for each network interface. This provides instant and automatic communication between all IPv6 host on a link. This feature is required in the lower layers of IPv6 network administration, such as for the Neighbor Discovery Protocol.

Private address prefixes may not be routed on the public Internet.

IP subnetworks

IP networks may be divided into subnetworks in both IPv4 and IPv6. For this purpose, an IP address is logically recognized as consisting of two parts: the network prefix and thehost identifier, or interface identifier (IPv6). The subnet mask or the CIDR prefix determines how the IP address is divided into network and host parts.

The term subnet mask is only used within IPv4. Both IP versions however use the CIDR concept and notation. In this, the IP address is followed by a slash and the number (in decimal) of bits used for the network part, also called the routing prefix. For example, an IPv4 address and its subnet mask may be 192.0.2.1 and 255.255.255.0, respectively. TheCIDR notation for the same IP address and subnet is 192.0.2.1/24, because the first 24 bits of the IP address indicate the network and subnet.

IP address assignment

Internet Protocol addresses are assigned to a host either anew at the time of booting, or permanently by fixed configuration of its hardware or software. Persistent configuration is also known as using a static IP address. In contrast, in situations when the computer's IP address is assigned newly each time, this is known as using a dynamic IP address.

Methods

Static IP addresses are manually assigned to a computer by an administrator. The exact procedure varies according to platform. This contrasts with dynamic IP addresses, which are assigned either by the computer interface or host software itself, as in Zeroconf, or assigned by a server using Dynamic Host Configuration Protocol (DHCP). Even though IP addresses assigned using DHCP may stay the same for long periods of time, they can generally change. In some cases, a network administrator may implement dynamically assigned static IP addresses. In this case, a DHCP server is used, but it is specifically configured to always assign the same IP address to a particular computer. This allows static IP addresses to be configured centrally, without having to specifically configure each computer on the network in a manual procedure.

In the absence or failure of static or stateful (DHCP) address configurations, an operating system may assign an IP address to a network interface using state-less auto-configuration methods, such as Zeroconf.

Uses of dynamic address assignment

IP addresses are most frequently assigned dynamically on LANs and broadband networks by the Dynamic Host Configuration Protocol (DHCP). They are used because it avoids the administrative burden of assigning specific static addresses to each device on a network. It also allows many devices to share limited address space on a network if only some of them will be online at a particular time. In most current desktop operating systems, dynamic IP configuration is enabled by default so that a user does not need to manually enter any settings to connect to a network with a DHCP server. DHCP is not the only technology used to assign IP addresses dynamically. Dialup and some broadband networks use dynamic address features of the Point-to-Point Protocol.

Sticky dynamic IP address

A sticky dynamic IP address is an informal term used by cable and DSL Internet access subscribers to describe a dynamically assigned IP address which seldom changes. The addresses are usually assigned with DHCP. Since the modems are usually powered on for extended periods of time, the address leases are usually set to long periods and simply renewed. If a modem is turned off and powered up again before the next expiration of the address lease, it will most likely receive the same IP address.

Address autoconfiguration

RFC 3330 defines an address block, 169.254.0.0/16, for the special use in link-local addressing for IPv4 networks. In IPv6, every interface, whether using static or dynamic address assignments, also receives a local-link address automatically in the block fe80::/10.

These addresses are only valid on the link, such as a local network segment or point-to-point connection, that a host is connected to. These addresses are not routable and like private addresses cannot be the source or destination of packets traversing the Internet.

When the link-local IPv4 address block was reserved, no standards existed for mechanisms of address autoconfiguration. Filling the void, Microsoft created an implementation that is called Automatic Private IP Addressing (APIPA). APIPA has been deployed on millions of machines and has, thus, become a de facto standard in the industry. In RFC 3927, the IETF defined a formal standard for this functionality.

Uses of static addressing

Some infrastructure situations have to use static addressing, such as when finding the Domain Name System (DNS) host that will translate domain names to IP addresses. Static addresses are also convenient, but not absolutely necessary, to locate servers inside an enterprise. An address obtained from a DNS server comes with a time to live, or caching time, after which it should be looked up to confirm that it has not changed. Even static IP addresses do change as a result of network administration (RFC 2072).

Conflict

An IP address conflict occurs when two devices on the same local physical or wireless network claim to have the same IP address – that is, they conflict with each other. Since only one of the devices is supposed to be on the network at a time, the second one to arrive will generally stop the IP functionality of one or both of the devices. In many cases with modern Operating Systems, the Operating System will notify the user of one of the devices that there is an IP address conflict (displaying the symptom error message) and then either stop functioning on the network or function very poorly on the network. If one of the devices is the gateway, the network will be crippled. Since IP addresses are assigned by multiple people and systems in multiple ways, any of them can be at fault.

Routing

IP addresses are classified into several classes of operational characteristics: unicast, multicast, anycast and broadcast addressing.

Unicast addressing

The most common concept of an IP address is in unicast addressing, available in both IPv4 and IPv6. It normally refers to a single sender or a single receiver, and can be used for both sending and receiving. Usually, a unicast address is associated with a single device or host, but a device or host may have more than one unicast address. Some individual PCs have several distinct unicast addresses, each for its own distinct purpose. Sending the same data to multiple unicast addresses requires the sender to send all the data many times over, once for each recipient.

Broadcast addressing

In IPv4 it is possible to send data to all possible destinations ("all-hosts broadcast"), which permits the sender to send the data only once, and all receivers receive a copy of it. In the IPv4 protocol, the address 255.255.255.255 is used for local broadcast. In addition, a directed (limited) broadcast can be made by combining the network prefix with a host suffix composed entirely of binary 1s. For example, the destination address used for a directed broadcast to devices on the 192.0.2.0/24 network is 192.0.2.255. IPv6 does not implement broadcast addressing and replaces it with multicast to the specially-defined all-nodes multicast address.

Multicast addressing

A multicast address is associated with a group of interested receivers. In IPv4, addresses 224.0.0.0 through 239.255.255.255 (the former Class D addresses) are designated as multicast addresses. IPv6 uses the address block with the prefix ff00::/8 for multicast applications. In either case, the sender sends a single datagram from its unicast address to the multicast group address and the intermediary routers take care of making copies and sending them to all receivers that have joined the corresponding multicast group.

Anycast addressing

Like broadcast and multicast, anycast is a one-to-many routing topology. However, the data stream is not transmitted to all receivers, just the one which the router decides is logically closest in the network. Anycast address is an inherent feature of only IPv6. In IPv4, anycast addressing implementations typically operate using the shortest-path metric ofBGP routing and do not take into account congestion or other attributes of the path. Anycast methods are useful for global load balancing and are commonly used in distributedDNS systems.

Public address

A public IP address, in common parlance, is a globally routable unicast IP address, meaning that the address is not an address reserved for use in private networks, such as those reserved by RFC 1918, or the various IPv6 address formats of local scope or site-local scope, for example for link-local addressing. Public IP addresses may be used for communication between hosts on the global Internet.

Modifications to IP addressing

IP blocking and firewalls

Firewalls perform Internet Protocol blocking to protect networks from unauthorized access. They are common on today's Internet. They control access to networks based on the IP address of a client computer. Whether using a blacklist or a whitelist, the IP address that is blocked is the perceived IP address of the client, meaning that if the client is using aproxy server or network address translation, blocking one IP address may block many individual computers.

IP address translation

Multiple client devices can appear to share IP addresses: either because they are part of a shared hosting web server environment or because an IPv4 network address translator(NAT) or proxy server acts as an intermediary agent on behalf of its customers, in which case the real originating IP addresses might be hidden from the server receiving a request. A common practice is to have a NAT hide a large number of IP addresses in a private network. Only the "outside" interface(s) of the NAT need to have Internet-routable addresses.

Most commonly, the NAT device maps TCP or UDP port numbers on the side of the larger, public network to individual private addresses on the masqueraded network.

In small home networks, NAT functions are usually implemented in a residential gateway device, typically one marketed as a "router". In this scenario, the computers connected to the router would have private IP addresses and the router would have a public address to communicate on the Internet. This type of router allows several computers to share one public IP address.

Internet service provider

"ISP" redirects here. For other uses, see ISP (disambiguation).

"Internet service" redirects here. It is not to be confused with Web service.

Internet connectivity options from end-user to tier 3/2 ISPs

An Internet service provider (ISP) is an organization that provides services for accessing and using the Internet. Internet service providers may be organized in various forms, such as commercial,community-owned, non-profit, or otherwise privately owned.

Internet services typically provided by ISPs include Internet access, Internet transit, domain name registration, web hosting, Usenet service, and colocation.

Internet services

World Wide Web

The World Wide Web (abbreviated WWW or the Web) is an information space where documents and other web resources are identified by Uniform Resource Locators (URLs), interlinked by hypertext links, and can be accessed via the Internet.[1]English scientist Tim Berners-Lee invented the World Wide Web in 1989. He wrote the first web browser computer programme in 1990 while employed at CERN in Switzerland.

The World Wide Web has been central to thedevelopment of the Information Age and is the primary toolbillions of people use to interact on the Internet.[4][5][6] Web pages are primarily text documents formatted and annotated with Hypertext MarkupLanguage (HTML). In addition toformatted text, web pages may contain images, video, audio, and software components that are rendered in the user's web browser as coherent pages of multimedia content. Embedded hyperlinks permit users tonavigate between web pages.Multiple web pages with a common theme, a common domain name, or both, make up awebsite. Website content can largely be provided by thepublisher, or interactive where users contribute content or the content dependsupon the user or their actions. Websites may be mostly informative, primarilyfor entertainment, or largely for commercial, governmental, or non-governmentalorganisational purposes. In the 2006 Great British Design Quest organised bythe BBC and the Design Museum, the World Wide Web was voted among the top 10British design icons.

Email.

Electronic mail, or email, is a method of exchanging digital messages between people using digital devices such as computers, tablets and mobile phones. Email first entered substantial use in the 1960s and by the mid-1970s had taken the form now recognized as email. Email operates across computer networks, which in the 2010s is primarily the Internet. Some early email systems required the author and the recipient to both be online at the same time, in common with instant messaging. Today's email systems are based on a store-and-forward model. Email servers accept, forward, deliver, and store messages. Neither the users nor their computers are required to be online simultaneously; they need to connect only briefly, typically to a mail server or a webmail interface, for as long as it takes to send or receive messages.Originally an ASCII text-only communications medium, Internet email was extended by Multipurpose Internet Mail Extensions (MIME) to carry text in other character sets and multimedia content attachments. International email, with internationalized email addresses using UTF-8, has been standardized, but as of 2016 it has not been widely adopted.[citation needed]The history of modern Internet email services reaches back to the early ARPANET, with standards for encoding email messages published as early as 1973 (RFC 561). An email message sent in the early 1970s looks very similar to a basic email sent today. Email played an important part in creating the Internet, and the conversion from ARPANET to the Internet in the early 1980s produced the core of the current services.

The symbol used for email

Social network

A social network is a social structure made up of a set of social actors (such as individuals or organizations), sets of dyadic ties, and other social interactions between actors. The social network perspective provides a set of methods for analyzing the structure of whole social entities as well as a variety of theories explaining the patterns observed in these structures.^[1] The study of these structures uses social network analysis to identify local and global patterns, locate influential entities, and examine network dynamics.

Social networks and the analysis of them is an inherently interdisciplinary academic field which emerged from social psychology,sociology, statistics, and graph theory. Georg Simmel authored early structural theories in sociology emphasizing the dynamics of triads and "web of group affiliations".  Jacob Moreno is credited with developing the first sociograms in the 1930s to study interpersonal relationships. These approaches were mathematically formalized in the 1950s and theories and methods of social networks became pervasive in the social and behavioral sciences by the 1980s. Social network analysis is now one of the major paradigms in contemporary sociology, and is also employed in a number of other social and formal sciences. Together with other complex networks, it forms part of then ascent field of network science.

Surfing to the Internet

Introduction:

Surfing the Internet is a term typically used to describe an undirected type of web of browsing where users whimsically follow one interesting link to another without a planned search strategy or definite objective. Surfing the net has become a popular pastime, for many Internet users.

Surfing the Internet' is not to be confused with the phrase 'browsing the Internet' which refers to exploring the web with a clear-cut objective but without any planned search strategies. Searching the web refers to exploring the Internet with a definite in both strategy and objective.

Surfing the Internet has been likened to the ironic term 'channel surfing', which is used to describe randomly changing TV channels. Its only relation to actual surfboarding has to do with the notion of 'going with flow' when surfing.

For more details about Internet surfing click the link bellow:

Surfing the internet

Using search engine

Introduction


You do not always have to know a website’s address in order to use the Internet. It is important to know how to search for information. One of the best methods to search is to use a search engine. A search engine is a software system on the Internet that will conduct a search of its own database of websites based on terms you have entered. As a result, you will be shown a list of web addresses that contain the term you were looking to find. An example of a popular search engine is www.google.com.
How to Use Google

First you will need to open Internet Explorer then enter www.google.com in the address bar. Here is what www.google.com looks like:

To conduct the search, point and click your mouse in the search textbox. Type in the textbox the words or words you would like to search. Then point and click your mouse on the Google Searchbutton below the search textbox.

As an example, the word ‘flowers’ was entered into the Google textbox and after clicking on the Google Search button these are the results:

Every phrase in either blue with an underline may be clicked on to visit that particular site. These are hyperlinks to websites. The websites deemed most fitting for the search are found at the near the top of the list. There are also paid sponsors found at the top (shaded) and to the right of the screen that you may visit if you wish. You can see actual web addresses in green text.

In addition, notice the results area:

These results are found on the top right of the page. 233,000,000 would be impossible to go through therefore you will need to learn ways to reduce the amount of results. To continue reviewing the search results pages, scroll to the bottom of the Google webpage until you see:

Click on the number 2 or on the blue arrow to the right to continue through the search results.

Important Notes:

You may not always get the results you are looking for so you will need to play with searchable terms. Using more words in combination, and especially more specific words will help. Be aware that not all websites that are found in the results are appropriate to your search. Read the blurb under the result name on the list before you click. In addition, do not click on anything that seems inappropriate, too good to be true, or dangerous. Use your gut instinct before you click. There are many websites out there on the Internet that will mislead and try to take advantage of beginners. Use caution.

Additional contents for finding Information on the Internet

Using Search Engines

There is an enormous amount of information on the Web! However, there's an easy way for you to find specific information without searching through every site yourself. Just use a search engine. Here are some tips to help you make the most of search engines

How to Use a Search Engine

Most search engines work the same basic way. You type into a search box the information you're looking for and PRESTO! the search engine lists Web sites that contain this information. These results are known as "hits." The words you type into the search box are called "keywords." The keywords you use will greatly affect your results. Other search engines, like Ask Jeeves for Kids, let you type in questions without having to choose keywords.

Four Tips to Help Make the Most of a Search

1.     Make your keywords as precise as possible. If you're looking for information on Tyrannosaurus rex, don't type in "dinosaurs." You'll get too much general information about dinosaurs and not enough specific hits about T-rex.

2.     Use two or more keywords in your search. But put the most important keywords first. For example, if you wanted information about what the T-rex ate, you might use the following keywords in this order: Tyrannosaurus rex diet. The search engine will look for Web pages that contain all these words.

3.     Make sure you spell the keywords correctly. If you typed "dinasour" as a keyword, your search would turn up empty. If you're not sure of a word's correct spelling, use a dictionary.

4.     Always try more than one search engine. Each search engine doesn't look through every site on the Web. Instead, most search engines check Web site pages every once in a while to create their own databases. So when you use a search engine, you're actually looking at one small slice of sites. Different search engines will usually come up with different results. So it makes sense to use more than one.

Three Tips for Getting More Precise Hits

1.     Use AND

Sometimes you may need to use more than one keyword when searching, without making a phrase. You usually need to let the search engine know whether you want to see sites that contain all the keywords or whether it should find those in which just one of the words appears. If you want to get results with all the keywords you type, then you should use "AND" to let the search engine know. Make sure you use capital letters when typing "AND."

Example: If you were searching for Web pages about dinosaurs and lizards, you would type:

The search engine will list sites that contain both words. Some search engines require a plus sign (+) instead of the word AND. Then you would add a plus sign before any keyword that must appear in your results:

2.     Use OR

Let's say you perform a search using two keywords. What can you do if you actually want to find Web sites in which either one word or the other appears? You can use the word "OR." This will let the search engine know you want Web sites that contain any of the keywords you type in. For the best results, you should always enclose OR searches in parentheses:

 The search engine will list Web sites that contain either keyword.

3.     Use NOT

Sometimes by typing one keyword, you'll get many results that have nothing to do with your topic. For example, if you wanted to find Web sites about dinosaurs, but not dinosaur fossils, you could type this into the search box:

The search engine will look for Web pages that contain the word "dinosaur." But if the page contains the word "fossil," the search engine will not list it. Some search engines require you to use a minus sign (-) in place of the word NOT. You would then add a minus sign in front of any word that you didn't want to appear in your results.

These types of searches are known as Boolean searches. AND (+), OR, and NOT (-) are known as Boolean operators. They are named after the British mathematician George Boole, who developed a system of logic in the 1800s.

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