Glossary

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Anonymous FTP: Anonymous File Transfer Protocol. A mechanism for moving files from a user machine to or from a remote Internet machine anonymously. In other words you do not have to identify yourself with a user name or password.
ARPANET: Advanced Research Projects Agency Network - The precursor to the Internet. It was created in 1969 by the US Department of Defence to conduct research into networking.
Backbone: A path through a network (such as the Internet) that has a very high capacity. By taking a large part of the network traffic over large distances it helps to speed up the network as a whole.
Bandwidth: A measure of how much data can be transmitted down any connection. For example a normal telephone line with the latest modems has a bandwidth of 56,000 bits per second.
Bps: Bits per second. A measurement of speed of data transfer from one place to another. For example a 56,000 bps 8 modem can process 56,000 bits per second.
Byte: The standard unit of measure for computer storage. It is the unit that holds a single character (in Western Alphabets) such as the letter "A" or the dollar sign "$". Languages such as Chinese and Japanese use two or more bytes for each character. Each byte consists of 8 bits to represent the character and one or more bits for internal computer purposes.
Cache: Pronounced "cash." A cache is stored files. For example, Web browsers often cache, or store, frequently visited Web sites so that the pages don't have to re-downloaded everytime you visit the same site. This speeds up the load-time for the Web pages.
Certificate: A document that is used to certify that a user or organisation is who they say they are. They contain information about who it belongs to, who it was issued by, expiration date and information that can be used to check out the contents of the certificate. It is as an important part of the SSL system for establishing secure connections.
Certificate Authority: An authority that issues Certificates needed to authenticate users or organisations on the Internet.
CGI (Common Gateway Interface): A CGI is a external program that can be run from a web browser. CGI's can be written in many different languages, the most common being C, C++, and Perl.
Cookie: A piece of information sent by a Web Server to a browser for storage on the client machine. The browser sends the information back to the Web Server when the latter requests it. This mechanism is used because the Web Server has no way of recognising a particular user when they revisit the site. In fact if you link from one page on the site to another on the same Web Site, the Web Server would not know that it is the same user looking at the two pages. On sites that you log on to, cookies are used to hold your id and password (so you don't have to log on each page!) On shopping sites the cookie could be used to keep a list of what you have bought so far, so that you can choose things as you see them rather than having to restate what you want when you get to the checkout.
DHTML: Dynamic HTML. Some features introduced in version 4 of HTML for making the Web pages more dynamic.
DHCP (Dynamic Host Configuration Protocol): A protocol used by a server/router that allows the client stations to be configured dynamically. The clients receive all their IP addresses, gateways, and DNS from the server/router, rather than having the settings statically configured on each client.
DNS ( Domain Name Service): The DNS server contains the records for domains. For example: The DNS records for seanet.com point www.seanet.com to the IP address 199.181.164.6.
Domain Name: Mapped to a particular numeric address. This takes the place of having to use an IP address number. Also, the name hierarchy on the Internet. Consists of a sequence of names separated by periods. Common extensions include: .com (commercial), .edu (education), .gov (government), and .org (organizations). Countries usually have their own extensions. For example, .ca (Canada) and .uk (United Kingdom).
DSL (Digital Subscriber Line): A high-speed access line that uses existing copper telephone wires.
DNS (Domain Name System): This is the "telephone directory" of the Internet. Under the cover the Internet works by giving each web site a unique address, known as the IP address. It is in the form of a series of digits separated by dots. When you click on a link or type in a URL, the Browser passes the URL to the Domain Name System. It looks up the URL (e.g. http://www.nmib.com) and obtains the IP address (in this case195.12.2.199) and passes it back to the Browser. The Browser uses the IP address to locate the web site. If you know the IP address you can type it in yourself, e.g. http://195.12.2.199.
E-commerce: Electronic Commerce is conducting commerce over the Internet, such as buying products or services from Web sites.
Encryption: Encoding information before it is transmitted over the Internet so that no one else can read it except the computer it is sent to.
Email: Electronic Mail is a mechanism for sending messages across a computer network. The text of the message is typed in on one computer and then is sent to someone else on the network. The recipient of the message reads it on his/her computer and can then delete the message, file it on the computer, print it, send a reply or forward it to other people on the network. Email is standard abbreviation for Electronic Mail. The software that processes your email is called an email program or an email reader. You can also use mailing lists to send a single message to many other users at the same time.
FAQs: Frequently Asked Questions. A set of questions with associated answers which set out to shed light on a particular subject area.
Firewall: A computer system that is used to prevent users on the Internet from getting unauthorised access to a LAN.
Flame Mail: Electronic Mail of an angry and often abusive nature. Typically sent to an Internet user who breaks the rules of one of the Newsgroups, by for example advertising when in a group that forbids it.
FTP: File Transfer Protocol. A mechanism for moving files between two machines over the Internet. An FTP site is a collection of documents, software, etc. which Internet users can transfer to their computers using FTP. The term anonymous ftp is used to refer to sites where no user id or password is needed to access the files. In other words the users are anonymous. FTP is also commonly used to transfer Web pages from the Webmaster's machine to the Web Server.
GIF: Graphic Interchange Format. One of the two standard formats used for image files on the Internet. The other standard format is JPEG. GIF format is well suited to diagrams and human created pictures and diagrams. It is also possible to do simple animations with the Animated GIF format.
Gigabyte: 1000 Megabytes, that is 1,000,000,000 bytes. The purists will tell you that it is actually the binary equivalent which is 1024 x 1024 x 1024!
Hit: A hit count is used as a measure of the popularity of a Web Page. One is added to the hit count every time anyone reads the page. Some pages publish their hit counts. The hit count for a Web Site is the sum of all the hit counts for each file that makes up the Web. This is used to measure the overall popularity of the Web Site and the load on the Web Server.
Home Page: A home page is the starting point for browsing a set of web pages. Every Web Site has a home page that is designed to be the first page seen. It typically has links to the various parts of the Web Site. A Browser also has a home page - the one that is displayed automatically when you invoke the browser. The leading browsers let you choose your own home page. So you can ensure that your starting point is your favourite search engine, directory or the home page of your own Web Site if you have one. The term is also used for a Web page created by an individual to say who they are and describe their interests, etc - e.g Jane Smith's home page.
HTML: HyperText Markup Language. The language used to create Web pages. It consists of a set of tags which indicate what action the browser should take when loading and processing the page.
HTTP: HyperText Transport Protocol. The language that Web Browsers use to communicate with Web servers. You will no doubt recognise HTTP as a part the address of web sites.
Hyperlink: A hyperlink is part of a web page that provides a link to another part of the World Wide Web. The words Link and Hypertext link are used interchangeably with Hyperlink.
Internet: The Internet (with a capital I) is a vast network of computers that straddles the world which is open for anyone to join. It hosts the World Wide Web and provides an Email connection for countless organisations and individuals. "internet" (with a lower case i) is a network that consists of two or more networks liked together. So the Internet is the most significant example of an internet.
Internet Service Provider: An Internet Service Provider is an organisation that offers Internet services including connection to the Internet and Web site hosting. Internet Service Providers are invariably referred to as ISP's.
IP Address: Internet Protocol Number. A number that is used to uniquely identify every computer on the Internet. It takes the following form:
189.104.232.8.
Whenever you type in a web address, the equivalent IP address is looked up in a directory and it is the IP address that is used to locate the relevant computer.
ISDN: Integrated Services Digital Network. A mechanism for using existing telephone lines to provide higher bandwidth communication. Unlike the normal use of telephone lines for transmitting data, there is no need for a modem. The data is transmitted digitally rather than being converted to analogue (and back to digital at the far end). This permits faster connections between computers and faster transmission.
ISP: An Internet Service Provider is an organisation that offers Internet services including connection to the Internet and Web site hosting. Internet Service Providers are invariably referred to as ISP's.
Java: Java is a programming language that is used for writing programs that can be downloaded to your computer through the Internet and immediately run within your browser. These programs are called Applets. Java is a portable language that runs on any computer supported by a piece of software called the Java Virtual Machine ( JVM for short). The popular browsers have a JVM built in and thus are capable of running Java Applets. Since Java is a complete programming language it is also used to create complete applications (independent of the browser) and programs to run on web servers.
JavaScript: A language that is embedded in Web pages. It is normally executed by the Browser as it displays the page. This can be used to make the Web page more dynamic and to validate the data that is typed into forms. On some web servers it can also be executed on the server to modify the page that is sent to the browser. In this context it cold for example be used to query a database and embed the results into the web page. Not to be confused with Java - which a different language.
JPEG: The Joint Photographic Experts Group (JPEG) format is one of the two standard formats used for images on the Web. The other is GIF. The JPEG format is well suited for photographic images.
JScript: Microsoft's name for its implementation of JavaScript.
Kilobyte: A thousand bytes. The purists will tell you that it is actually the binary equivalent, which is 1024!
LAN: Local Area Network. A computer network situated within a given locality, typically one building or one site.
Mailing List: A mechanism for sending copies of a single Email note to more than one recipient. The copies can be made on the user's machine. Alternatively a single copy is send to a server on the Internet for copying and sending on to the list of recipients. There are thousands of mailing lists operated on the Internet on all imaginable topics.
Megabyte: A million bytes. The purists will tell you that it is actually the binary equivalent, which is 1024 x 1024!
MIME: Multipurpose Internet Mail Extensions. The standard used on the Internet for identifying different types of file. It was initially introduced for attaching files to Internet Email messages, but is also used by Web Servers to inform browsers what type of file they are sending. Examples of MIME types are "text/html" for standard Web pages and image/jpeg for JPEG files. Recent browsers and Email systems handle a large number of MIME types automatically.
Mirror Sites: A Mirror site of a Web site is an exact copy of the original site. They are commonly used for Web and FTP sites when the original site cannot cope with the load that is being put on it. An added benefit can be that one of the mirror sites is more accessible to you and therefore provides faster access.
Modem: Modulator demodulator. A device that is used to transmit data between two computers over a normal telephone line. You have one modem at each end of the phone line. At the sending end the data is converted into an analogue signal so that the telephone system can handle it, and at the receiving end the analogue system is converted back to digital form so that the computer can handle it.
Network: Two or more computers connected together so that from one computer you can access data or run software on another computer.
Newbie: A person who is new to the Internet.
Node: Any single computer on a network. Sometimes also referred to as hosts.
Password: The password is a string of characters that only you know. The password is used to stop other people masquerading as you. Sometimes the computer will check that not only have you typed the correct password in but that each letter is also in the correct case (upper or lower). To be effective a password needs to be a string of characters that no one else could guess. So your name, initials, initials in reverse order are not good passwords. Mixing case and adding characters other than letters of the alphabet will help. So something like AZ9%3cG would be quite secure, the only problem being that you have to be able to remember it.
Perl: A programming language that is often used to write programs that run on Web Servers.
Portal: A web site that sets out to provide a point of entry to the World Wide Web. Examples are Yahoo and Netscape Netcenter. They provide a wide selection of services (such as free email) and links to the rest of the Web. Their goal is to become your browser home page - the page that appears automatically each time you load your browser, or when you click on the home button.
Post Office Protocol: One of the standard protocols used by your Email software when accessing Email from the Internet. If your Internet Service Provider only supports POP, then you will need Email software that can handle that protocol. The version number is often tagged on the end. Thus POP3 is version 3 of the post office protocol.
Protocol: A language used to communicate between two computer programs. It consists of a set of commands and the rules about how they are used. A major cause of the success of the Internet has been the widespread adoption of a number of protocols, such as HTTP for communicating with Web Servers, FTP, etc.
Router: A computer at a junction on the Internet that directs data towards its correct destination. They decide which link of the network to send the data based on the IP number of the destination computer.
Server: A computer that provides a service to other computers on the network. For example a Web Server obtains web pages and other files as requested by a Web user and sends them to the browser. The term server is also applied to software packages that provide a service - so you also have Web Server software for example. The machines that connect to the Server and use the services it offers are known as Client machines.
SMTP: Simple Mail Transport Protocol. The protocol used to send electronic mail over the Internet.
Spam (or Spamming): The Email equivalent of junk mail. The term is used in particular to describe the practice of sending the same message to a number of different Usenet groups or mailing lists. Some groups and mailing lists have rules against spamming, and offenders can get bombarded with flame mail. An inappropriate attempt to use a mailing list, or USENET or other networked communications facility as if it was a broadcast medium (which it is not) by sending the same message to a large number of people who didn’t ask for it. The term probably comes from a famous Monty Python skit which featured the word spam repeated over and over. The term may also have come from someone’s low opinion of the food product with the same name, which is generally perceived as a generic content-free waste of resources. (Spam is a registered trademark of Hormel Corporation, for its processed meat product.)
Secure Sockets Layer (SSL): A protocol that supports secure communication over the Internet. SSL supports authentication and encryption. Authentication provides via certificates a means for you to validate who you are in contact with. Encryption codes all the data before it is transmitted, making it impossible for anyone else on the Internet to intercept and read your communications. This is important for shopping on the Web. It allows you check that the Web site is in fact owned by Dell Computers, and you can send your credit card details without fear that someone else on the Internet will see them.
Streaming: Streaming audio or video is an audio or video is a technique which allows an audio signal to be listened to and a video signal to viewed while it is being transmitted from a Web site. This contrasts with the technique of transfering the whole file before it starts playing back to you. Streaming requires that the signal is transmitted as fast as you view it. To achieve this the quality is sacrificed when a slow connection is being used.
TCP: Part of the TCP/IP suite of protocols used to communicate between machines on the Internet. On the sending computer TCP splits the data up into manageable sized packets and attaches information such as the IP number of the target computer. At the receiving computer it checks all the packets have arrived and issues a request to resend a packet if necessary. When they have all arrived it extracts the data from each packet and assembles it in the correct sequence.
See also TCP/IP, IP Number
TCP/IP: Transmission Control Protocol/Internet Protocol. A set of protocols that are used by computers on the Internet to communicate with each other. It is used by all computers on the Internet or any Intranet.
Telnet: An Internet service that allows you to log into a remote computer.
Terabyte: 1000 gigabytes. The purists will tell you that it is actually the binary equivalent which is 1024 x 1024 x 1024 x 1024!
URL: Uniform Resource Locator. The mechanism for addressing resources on the Internet. Uniform Resource Locator is invariably abbreviated to URL. The URL is best known for specifying Web addresses. For example the URL for this glossary is "http://www.nmib.com/glossary/index.htm". This is what you type into the address field in the browser.
VBScript: Visual Basic Script. A language that is embedded in Web pages and is executed by the Browser as it displays the page. It can be used to make the Web page more dynamic and to validate the data that is typed into forms. It serves the same purpose as JavaScript. It is a subset of Visual Basic with one or two additions!
Virus: A virus is computer code, that is hidden within a program, and copies itself to other programs. They are created by programmers who either want to see what they can achieve or who have a malicious intent. Usually the virus manifests itself at some stage, often triggered on a pre-specified date. Some manifest themselves simply by displaying a message on the screen, others corrupt the contents of the machine on which they are running.
WAN: Wide Area Network - A computer network that is spread over more than one location, e.g. linking offices of a company around the world.
Web: Short for World Wide Web. Since the words "world wide" are omitted it is equally appropriate for an Intranet and the Internet.
Webmaster: The person who is responsible for maintaining a Web site. The term webmaster may be used for both men and women.
Web Page: A document that is stored in HTML format. It can contain text, images and hyperlinks. Web pages are usually grouped with other pages on the same theme to form a Web site.
Web Server: A computer that manages a Web site. It passes Web pages to browsers when they request them. The Web pages are often stored on the Web server but could be on another computer on the same network as the Web Server.
Web Site: A collection of Web pages which represent an organisation, individual or subject area. Many companies have their own Web sites, typically containing information on how to contact them and products and services. Each web site has a home page which is the normal starting point for people visiting the site.
Web Space: The disk space on a Web Server that is set aside for a Web site.
World Wide Web: A service that runs on the Internet that allows information to be stored in a great variety of formats (including text, pictures, sound and video). It also provides an easy way to link from one page of information to another simply by pointing with the mouse and clicking. The World Wide Web is often abbreviated to WWW or simply the Web.
W3C (World Wide Web Consortium): The organization that is responsible for developing the standards (such as HTML, HTTP and XML) that are needed for the World Wide Web. Often abbreviated to W3C.
XML: Extensible Markup Language. A subset of SGML that has been developed for describing data. It is becoming the standard format for sending data over the Internet.