ProperGander

Security for the masses

What is the Internet?

The Internet is basically computers connected to computers in what are called networks, and networks connected to networks. To describe how it works I thought of this analogy; Think of your telephone, the phone connected to a land line, it has a handset(Microphone and speaker) and a dialer usually push button number pad which allows you to type a number to connect to another phone. When you dial a number your phone is connected to the phone which has been assigned the number you dial. The phone you connect to can be anywhere on the planet. All telephones have a unique number, a telephone number. All telephones globally are connected to each other through telephone exchanges, buildings full of switches. When you dial a number a sequence of switches are switched on to connect your phone to the phone that has the number you dial.

The Internet works in a similar way. Each computer connected to the Internet has its own unique number similar to a telephone number. This number that uniquely identifies computers is an IP (Internet Protocol) address. Just like the telephone system, computers connect to each other by requesting (dialing) the IP address of the computer they wish to connect to. The job of the telephone exchange is done by devices on the Internet called routers and just as telephone exchanges route your phone to another phone by flipping switches, routers route your computers connection request to the IP address of the destination computer. This connection request may have to go through several routers before reaching the desired computer, each router the request passes through is known as a hop.

Each router on the Internet is aware of all the addresses to which itself can connect to directly, and it is also aware of which connections lead to other addresses to which it is not connected directly. All this information is stored in a lookup or configuration table inside the router. If the IP address of the computer you want to connect to is not in that list, the router forwards the connection request to another router it believes does know how to connect to the destination computer. Eventually after several hops or router connections the computers connect to each other. This is a somewhat over simplified explanation of how computers communicate with each other.
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What is the World Wide Web?

The World Wide Web is the name given to the entire part of the Internet you can see with your web browser. Firefox, Microsoft Internet Explorer, Safari and Opera are the most popular web browsers. The World Wide Web, or WWW or Web for short, consists of millions of web sites, sites just like this one: propergander.org.uk as well as yahoo.com and theregister.co.uk amongst millions of others.

Websites contain web pages. A web page is what you are viewing now. It's a plain text file which can contain links to imgages, sound or video amongst other things which are embedded in the page when viewed in a browser. Web pages are written to comply with HTML (HyperText Markup Language) standards and contain tags, words in angled brackets which browsers interpret as instructions on how to display the page.
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What is a 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. Hyperlinks present in resources enable users to easily navigate their browsers to related resources.

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 Mozilla Firefox, Opera, Apple Safari, Google Chrome and Internet Explorer.

What is E-mail?

Email (Electronic mail), is a way of exchanging messages. Email systems are based on a store-and-forward model in which email computer server systems accept, forward, deliver and store messages on behalf of users for the duration of message submission or retrieval. Rarely is e-mail transmitted directly from one user's computer to another. An email message consists of two parts, the message header and the message body. The body is the email content. The message header contains information such as an originator's email address and one or more recipient addresses and usually a subject line.
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The most widely used email clients are Mozilla Thunderbird, Evolution, KMail and Outlook Express.

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