Email

Electronic mail, commonly known as email or e-mail, is a method of exchanging digital messages from an author to one or more recipients. Modern email operates across the Internet or other computer networks. Some early email systems required that the author and the recipient 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 connect only briefly, typically to an email server, for as long as it takes to send or receive messages.
An email message consists of three components, the message envelope, the message header, and the message body. The message header contains control information, including, minimally, an originator's email address and one or more recipient addresses. Usually descriptive information is also added, such as a subject header field and a message submission date/time stamp.
Originally a text-only (7-bit ASCII and others) communications medium, email was extended to carry multi-media content attachments, a process standardized in RFC 2045 through 2049. Collectively, these RFCs have come to be called Multipurpose Internet Mail Extensions (MIME).
Electronic mail predates the inception of the Internet, and was in fact a crucial tool in creating it,^[2] but the history of modern, global Internet email services reaches back to the early ARPANET. Standards for encoding email messages were proposed as early as 1973 (RFC 561). Conversion from ARPANET to the Internet in the early 1980s produced the core of the current services. An email sent in the early 1970s looks quite similar to a basic text message sent on the Internet today.
Network-based email was initially exchanged on the ARPANET in extensions to the File Transfer Protocol (FTP), but is now carried by the Simple Mail Transfer Protocol (SMTP), first published as Internet standard 10 (RFC 821) in 1982. In the process of transporting email messages between systems, SMTP communicates delivery parameters using a message envelope separate from the message (header and body) itself.

How Internet Search Engines Work

Internet search engines are special sites on the Web that are designed to help people find information stored on other sites. There are differences in the ways various search engines work, but they all perform three basic tasks:

• They search the Internet -- or select pieces of the Internet -- based on important words.
• They keep an index of the words they find, and where they find them.
• They allow users to look for words or combinations of words found in that index.

Early search engines held an index of a few hundred thousand pages and documents, and received maybe one or two thousand inquiries each day. Today, a top search engine will index hundreds of millions of pages, and respond to tens of millions of queries per day. In this article, we'll tell you how these major tasks are performed, and how Internet search engines put the pieces together in order to let you find the information you need on the Web.

Web search engine

A web search engine is designed to search for information on the World Wide Web and FTP servers. The search results are generally presented in a list of results often referred to as search engine results pages (SERPs). The information may consist of web pages, images, information and other types of files. Some search engines also mine data available in databases or open directories. Unlike web directories, which are maintained only by human editors, search engines also maintain real-time information by running an algorithm on a web crawler.

Timeline (full list)
Year	Engine	Current status
1993	W3Catalog	Inactive
	Aliweb	Inactive
1994	WebCrawler	Active, Aggregator
	Go.com	Active, Yahoo Search
	Lycos	Active
1995	AltaVista	Inactive (URL redirected to Yahoo!)
	Daum	Active
	Magellan	Inactive
	Excite	Active
	SAPO	Active
	Yahoo!	Active, Launched as a directory
1996	Dogpile	Active, Aggregator
	Inktomi	Acquired by Yahoo!
	HotBot	Active (lycos.com)
	Ask Jeeves	Active (ask.com, Jeeves went away)
1997	Northern Light	Inactive
	Yandex	Active
1998	Google	Active
	MSN Search	Active as Bing
1999	AlltheWeb	Inactive (URL redirected to Yahoo!)
	GenieKnows	Active, rebranded Yellowee.com
	Naver	Active
	Teoma	Active
	Vivisimo	Inactive
2000	Baidu	Active
	Exalead	Acquired by Dassault Systèmes
2002	Inktomi	Acquired by Yahoo!
2003	Info.com	Active
2004	Yahoo! Search	Active, Launched own web search (see Yahoo! Directory, 1995)
	A9.com	Inactive
	Sogou	Active
2005	AOL Search	Active
	Ask.com	Active
	GoodSearch	Active
	SearchMe	Closed
2006	wikiseek	Inactive
	Quaero	Active
	Ask.com	Active
	Live Search	Active as Bing, Launched as rebranded MSN Search
	ChaCha	Active
	Guruji.com	Active
2007	wikiseek	Inactive
	Sproose	Inactive
	Wikia Search	Inactive
	Blackle.com	Active
2008	Powerset	Inactive (redirects to Bing)
	Picollator	Inactive
	Viewzi	Inactive
	Boogami	Inactive
	LeapFish	Inactive
	Forestle	Inactive (redirects to Ecosia)
	VADLO	Active
	Duck Duck Go	Active, Aggregator
2009	Bing	Active, Launched as rebranded Live Search
	Yebol	Active
	Megafore	Active
	Mugurdy	Inactive due to a lack of funding
	Goby	Active
2010	Black Google Mobile	Active
	Blekko	Active
	Cuil	Inactive
	Yandex	Active, Launched global (English) search
	Yummly	Active
2011	Interred	Active
2012	Volunia	Active , only Power User
	Goorbe	Active, only Persian Language

Uniform resource locator

In computing, a uniform resource locator (URL) is a specific character string that constitutes a reference to an Internet resource.
A URL is technically a type of uniform resource identifier (URI) but in many technical documents and verbal discussions URL is often used as a synonym for URI

Web Browser

A web 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) and may be a web page, image, video, or other piece of content.^[2] Hyperlinks present in resources enable users easily to navigate their browsers to related resources. A web browser can also be defined as an application software or program designed to enable users to access, retrieve and view documents and other resources on the Internet.
Although browsers are primarily intended to access 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, Opera, and Safari

ADSL

Commonly simplified as DSL, Asymmetric Digital Subscriber Line (ADSL) is technology for high-speed Internet access. It uses existing copper telephone lines to send and receive data at speeds that far exceed conventional dial-up modems, while still allowing users to talk on the phone while they surf. By contrast, DSL is typically not as fast as cable Internet access. It is generally well-suited for moderate gaming, computer-aided design, streaming multimedia, and downloading large files.

ADSL Speed

The fastest dial-up modems are rated at 56 kilobits per second (Kbps), and usually operate at about 53 Kbps under good conditions. By comparison, ADSL allows download speeds from 1.5 to 8 megabits per second (Mbps), depending on the grade of DSL service purchased. Cable Internet is capable of supporting up to 30 Mbps.

How Does ADSL Work?

ADSL uses standard telephone lines to upload and download data on a digital frequency, which sets these datastreams apart from the analog signals that telephones and fax machines use. The telephone can be used at the same time when surfing the Web with DSL service because the signal is operating on a different frequency; this is not true of conventional dial-up Internet access. It may be necessary to install inexpensive filters on each phone or fax line to remove any "white noise" on the line that might be generated from the DSL signals.

What Is DSL

The full form of DSL is known as the digital subscriber line, which consists of various different technologies that provide an internet connection to a computer network using the DSL.
The digital subscriber line , or most commonly known as the DSL, involves the use of the pair of copper phone lines using the wiring networks, these also comprise of a main switch which has special hardware to relay the internet signals to the other end of the user. A continuous digital connection network can be achieved using this technology.
The DSL technology is purely based on digital composition and thus there is no use of the digital to analog conversion for the internet transmission as required in the previous modems of the traditional times. The DSL system does not use the frequency spectrum of the audio in the phone, because it requires the frequency above that which means that the telephone can be used while the internet connection is still on.
The speed of the DSL system technology is incomparable to any other internet connection provider, previously used. If compared, the DSL wins over 50 times faster inter speed than the general modems used and is about 12 times faster than the ISDN connection. The reason behind this is that the DSL system used different frequencies for the encoding of the data, which allows a much faster internet speed. Another factor which contributes to the high speed of the DSL is that it is not a bus technology because of which its offered bandwidth is much more consistent than the other types of modems which provides the same bandwidth to multiple users.
However, the only conditions that can affect the transmission speed are the wiring conditions and also to some extent the distance limitations.

Internet tools

Internet tools are basically used so as to make the internet use much easier via some of the applications specially made for a particular internet business.

These tools are advanced and custom-built for the development of the internet, so that the optimal management can be achieved both in the informational and communication solutions. These tools are also available commercially.

Different networks are compatible with different internet tools, as described further.

The tools related to the networking of the TCP/IP most widely used is the "Fifi Ping »"

The Ping is actually used for the basic inquiry to determine whether the host which is governing the internet is alive and transmitting information and signals or not. The ping tool performs this task by sending data to the host of the network used for the internet so as to see the response and the time period required to achieve it.

The internet tool of the "Icestorm NSLookup »" is used to convert your personal domain name into an IP or the internet protocol address, like the form (216.122.237.109) it can then be used for exactly the opposite task, but the DNS server has to be queried for that.

The other internet tool related with the Internet protocol "Dig DNS Check »" is used to gain information from the DNS servers using the domain information groper of the DIG.

The internet tool of the "logic Host Check »" is used by the network of TCP/IP to perform several different tasks and tools of the network in one single host.

What is Internet

he internet in simple terms is a network of the interlinked computer networking worldwide, which is accessible to the general public. These interconnected computers work by transmitting data through a special type of packet switching which is known as the IP or the internet protocol.

Internet is such a huge network of several different interlinked networks relating to the business, government, academic, and even smaller domestic networks, therefore internet is known as the network of all the other networks. These networks enable the internet to be used for various important functions which include the several means of communications like the file transfer, the online chat and even the sharing of the documents and web sites on the WWW, or the World Wide Web.

It is always mistaken said that the internet and the World Wide Web are both the same terms, or are synonymous. Actually there is a very significant difference between the two which has to be clear to understand both the terms. The internet and World Wide Web are both the networks yet; the internet is the network of the several different computers which are connected through the linkage of the accessories like the copper wires, the fiber optics and even the latest wireless connections. However, the World Wide Web consists of the interlinked collection of the information and documents which are taken as the resource by the general public. These are then linked by the website URLs and the hyperlinks. Therefore World Wide Web is one of the services offered by the whole complicated and huge network of the internet.

The use of IP in the Internet is the integral part of the network, as they provide the services of the internet, through different layers organization through the IP data packets. There are other protocols that are the sub-classes of the IP itself, like the TCP, and the HTTP.

Introduction To Building Your Own PC

This is an introduction to building your own custom gaming computers to play the latest games. Building your own PC is the way to go if you want the best performance for gaming, and at the best value. Despite what some people may tell you, it is quite straightforward and easy to do.
If this is your first time building a custom computer, building custom gaming computers simply involves selecting and buying all your computer components separately and then installing them one by one. If you choose the right parts you will end up with a fast, cost-effective gaming computer capable of playing the latest PC game releases.

Advantages to Building Your Own

There are many good reasons to go custom. These are the main advantages of building your own custom gaming PC as opposed to buying a pre-built system:

• Better performance. If you want a high-performance gaming PC tailored to your gaming needs, building your own machine is the best way to go about it.
• Save money. By shopping around for quality components at good prices you can save quite a bit of money. Building a custom gaming PC is usually a lot more cost-effective than buying a pre-built system.
• Learning Experience. Whilst choosing your components and building your gaming computer, you are bound to learn a lot of valuable information about PC hardware and how computers work on the inside.

As you can see, there are great reasons why someone would want to build their own custom gaming computer. On top of all that, you will feel great after having built your own custom machine all by yourself.
If you haven't built your own machine before, I would definitely encourage you to build your next setup. No matter what some people say, it really isn't difficult at all and the money you will save is quite significant for most people.
These days installation is a breeze and for the majority of the parts it's simply a matter of following the instructions that came with it.

Choosing Your Components

How do you go about choosing the right components for your needs? How do you know which component is best for you? How do they all work together?The following buying guides for each component will hopefully clear up the confusion on what you need to know to choose the best parts for your custom gaming build. Or if you're looking for specific part recommendations you can skip to the Recommended Gaming Desktop Computer Builds.

Choosing the Best Motherboard For Your Custom Gaming PC

This article is here to help you choose the best motherboard for gaming. The motherboard is one of the most important components in any computer, and it can make or break a system.
You can have the best CPU, RAM, and graphics card in the world, but without a quality motherboard at the core of your system you won't be getting anywhere fast.

We will look at the various factors you should take into account when choosing your gaming motherboard, to ensure that you choose the best motherboard for your needs and one that is compatible with all your other components.
If you think of the processor as the brain of a computer, then the motherboard could be described as the heart and/or central nervous system. The motherboard represents the core of a PC and is responsible for relaying information between all the internal components. In other words, it’s the hub of the computer, where all other components connect to.
Since the motherboard is so crucial to your system, buying the best motherboard you can afford is a good investment if you want a gaming system that will last. The following guidelines are here to help you make a more informed decision on your gaming motherboard choice:

CPU Compatability
The first thing you need to be aware of when choosing a motherboard is compatability with the CPU you plan on using. A motherboard will generally only support either Intel or AMD CPUs, and only certain models too.
Checking for compatability between a particuilar motherboard and a CPU is very simple, all you need to do is check to see if the motherboard and CPU both have the same 'processor interface'.

RAM Compatability
The motherboard you choose will dictate the type and amount of RAM you can have. These days you will want to get DDR3 RAM, and at least 4GB for the best gaming performance to play the latest games. So ensure your motherboard will support this type and amount of memory, but most boards these days will so it's very rarely an issue.

Ports, Slots, and Other Features
If you need extra PCI ports for other cards then make sure your motherboard has this. You should also consider the number of USB ports you need, and whether you need a Firewire port (used for video capturing and editing).
Also, be sure there's enough PCI-Express slots for your needs. You will need a PCI-Express slot for your video card, or two slots if you are going to install two video cards in your machine. If you decide on getting a dedicated sound card then you will need another PCI-Express port for that too.

On-board Audio VS Dedicated Sound Card
Most motherboards will come with built-in audio so getting a dedicated sound card is completely optional. I would recommend investing in a sound card if you want the very best experience from your games, or if you want to take full advantage of high quality speakers or headphones.
For music producers and those doing video and audio editing it's a different story, and a sound card is necessary as the on-board sound provided by typical motherboards won't cut it. If you want to learn more about choosing a dedicated sound card for gaming or other purposes check out How To Choose The Best Sound Card.

Tips On Buying Your Motherboard
When you're choosing the best motherboard for your gaming PC it's wise to think ahead a little. If you want your motherboard to last you a while then I would recommend you choose a decent quality board that has been released recently.
Since the motherboard is such a critical component to your gaming PC, in general I would recommend buying the best board you can afford. Some of the most-trusted motherboard manufacturers for quality and reliability are ASUS, MSI, EVGA, Intel, and Gigabyte to name a few of the best.
If you are looking for specific recommendations on the best motherboards for use gaming, check out the Recommended Custom Gaming Builds. The motherboards picked in those builds are some of the best available right now with both high performance and value for money in mind, and we strive to always keep them updated from month to month.

IP address (Internet Protocol Address)

The Internet Protocol (IP) is the method or protocol by which data is sent from one computer to another on the Internet. Each computer (known as a host) on the Internet has at least one IP address that uniquely identifies it from all other computers on the Internet.

When you send or receive data (for example, an e-mail note or a Web page), the message gets divided into little chunks called packets. Each of these packets contains both the sender's Internet address and the receiver's address. Any packet is sent first to a gateway computer that understands a small part of the Internet. The gateway computer reads the destination address and forwards the packet to an adjacent gateway that in turn reads the destination address and so forth across the Internet until one gateway recognizes the packet as belonging to a computer within its immediate neighborhood or domain. That gateway then forwards the packet directly to the computer whose address is specified.
Because a message is divided into a number of packets, each packet can, if necessary, be sent by a different route across the Internet. Packets can arrive in a different order than the order they were sent in. The Internet Protocol just delivers them. It's up to another protocol, the Transmission Control Protocol (TCP) to put them back in the right order.
IP is a connectionless protocol, which means that there is no continuing connection between the end points that are communicating. Each packet that travels through the Internet is treated as an independent unit of data without any relation to any other unit of data. (The reason the packets do get put in the right order is because of TCP, the connection-oriented protocol that keeps track of the packet sequence in a message.) In the Open Systems Interconnection (OSI) communication model, IP is in layer 3, the Networking Layer.
The most widely used version of IP today is Internet Protocol Version 4 (IPv4). However, IP Version 6 (IPv6) is also beginning to be supported. IPv6 provides for much longer addresses and therefore for the possibility of many more Internet users. IPv6 includes the capabilities of IPv4 and any server that can support IPv6 packets can also support IPv4 packets.