A small java application designed to run on a web page. Java is a programming language that can be used to produce games and utilities such as currency converters. Applets are downloaded by your browser and run on your computer.

Arpanet

The Advanced Research Project Agency NETwork. Arpanet was a military network built by the US government at the height of the Cold War, and was designed to withstand a possible nuclear attack. Arpanet was the forerunner to today's Internet.

Backbone

The main data highway that carries enormous numbers of bits and bytes around the world. These are the high speed connections that cross the globe and form the top level of the network hierarchy that in turn forms the Net.

A program designed to search the Net for information automatically. Many of the search engines use bots to scout the Net for URLs and appropriate keywords to include in their database. There are also IRC Bots, and Bots designed by hackers to do various tasks.

Client Server

Describes the relationship between two different computers. One computer, the client, requests information from another computer, the server. The server gives, the client takes. When you access a web page, your client computer requests that page from a web server.

Domain Name

Identifies a computer connected to the Net. Domain names typically consist of a host name such as netmag, followed by a top level domain category, such as .com, .co, .org, and then perhaps a country abbreviation, like uk. Domain names are easy to remember aliases for numerical IP addresses.

Domain Name Systems

A bit like a phone book of Internet addresses. Every Net address or, to use its proper name, IP address, consists of a series of digits, such as 194.217.172.1. It isn't easy to remember a series of digits, for each website you want to visit, so the Domain Name System was created. This is a database system that looks up Internet addresses based upon domain names.

Download

When you downloading something from the Net – web page or a piece of software – you are transferring it to your computer from another computer.

File Transfer Protocol (FTP)

A protocol that enables files to be transferred between computers on the Internet. You can download files from web pages, but FTP is a more efficient means of doing it.

Firewall

A security setup that prevents unauthorized users gaining entry to a private network, such as a corporate network.

Gateway

A computer that controls access on to the Internet – for example, you'll go through a gateway computer to get to the Net from your company's local area network. This means your system administrator can monitor all your Net activities – so watch out.

A connection between computers during the transfer of information across the Net. Data travels on the Net from computer to computer – from your computer, to your ISP's, to a web site computer, and so on. Depending on computer activity around the world, there can be any number of hops between you and, say, a web page you want to retrieve. The more hops there are, the longer it will take to retrieve information.

Hypertext Markup Language (HTML)

The mark-up language used to create web pages. HTML consists of formatting commands which a browser reads, and then uses to display the web pages accordingly.

Hypertext Transfer Protocol (HTTP)

The protocol used to transfer HTML documents across the Net. When there's an ‘s' on the end, giving https at the start of a web address, you have accessed a secure server and are transferring files securely.

Off Line

When you are not connected to the Internet.

When you are connected to the Internet.

Or packet InterNet Groper, to be precise. It's a small program that can send a test message to a server to see whether it exists.

A computer that redirects data – your ISP has a router that'll send your Net requests in the right direction. Also known as a switch.

A computer that handles requests from client machines. Mail servers deliver mail, FTP servers give out files, web servers store web pages.

Secure Server

A computer that handles encrypted data for secure transactions, for example, when you buy something online you are connected to a secure server so your credit card details cannot be read by anyone else.

To transfer data from your computer to another computer.

Uniform Resource Locator – another way to say web site address.