Dictionary of computer and Internet terms

To achieve benefits from IT, users and IT specialists must be able to understand each other. We use tools like this dictionary to achieve mutual understanding.

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Active X control Screen item (e.g. a scrollable grid for allowing multi-line data entry) downloaded from a website into a browser and run from the browser on the user's PC. Users may refuse to accept Active X controls because they are written in full-strength programming languages and therefore by mischief or accident can cause serious damage to files on users' PCs.
See the notes on "Applet" and "Plug-in".

Applet Miniature application program downloaded from a website into a browser and run from the browser on the user's PC.
Users may refuse to accept applets because they are written in full-strength programming languages and therefore by mischief or accident can cause serious damage to files on users' PCs.
See the notes on "Active X control" and "Plug-in".

ASP Active Server Pages, a system which provides:

A programming language which can be used to produce dynamic web pages.
An application server program (see "server") which runs programs written in the ASP language.

Bookmark Make your browser save the URL and title of a web page so you can easily find it again.

Browser Program which presents information from any website (chosen by the user) - usually runs on a PC. There are dozens of browser programs but a recent survey concluded that:

the vast majority of users use Microsoft's Internet Explorer on some version of Windows
almost all the rest use Netscape's Navigator / Communicator on some version of Windows.

C++ Programming language which is used for writing operating systems, high-speed games and other programs which need speed and / or the ability to use all the facilities of the operating system. Too complex to be an economical tool for developing most commercial and administrative systems - Visual Basic and a number of other languages are generally better for this.

Chromeless window A browser window which has none of:

Toolbar - so no Back and Forward buttons.
Menu bar.
Address / location bar.
Status bar.
so the user has almost no control over what happens.
Usually a very bad design technique.

ColdFusion A system which provides:

A programming language which can be used to produce dynamic web pages.
An application server program (see "server") which runs programs written in the ColdFusion language.

Cookie A file stored on a PC by the browser and sent to the relevant web site with each page request. Often used by websites to maintain details of the user from one session to another.
Sometimes used to make life easier for the user, too often used to push advertising at the user.
Some users set their browsers to prevent websites from storing cookies.

Data model The first stage of database design. It's important to get this right because errors are likely to mean that:

You won't be able to store, retrieve and cross-refer data in the way you need.
If you change the database structure to remedy these problems, you'll also have to change all programs which read or update the changed part of the database and perhaps others which implicitly assume that the database is structured in the old way.

Default page
(of a website) The page which is displayed if the visitor does not specify a page. The name depends on how the website is set up but is most commonly "index.htm" If there is no default page or the website does not recognise a page which is present as being the default page, visitors see a directory listing rather like Windows Explorer's - not usually desirable, especially if you want visitors to register or to provide a user id and password before they can see the rest of the site.

DHTML Dynamic HTML, an extension of HTML which allows the page to vary what it shows and how it behaves in a limited way depending on the circumstances. We say "limited" because if a page is built using only DHTML the underlying content of the page is always the same so it will always display the same set of contents and behaviours - see the note on "Dynamic web pages".

Domain The part of a URL which identifies the site, for example in www.mywebsite/mypage.htm "mywebsite" is the domain name. There's been a mad scramble for attractive domain names in recent years and it's getting increasingly difficult to find one which is not already taken and not too similar to one which is already taken.

Dynamic web pages Pages whose whole content varies depending on the circumstances, usually on the results of searches in a database. Dynamic web pages are an essential part of e-commerce applications, e.g. to display the goods / services in a firm's catalogue, to keep track of the list of items the visitor has chosen and to enable the visitor to pay for these items. It's very difficult to build dynamic web pages without using a tool such as ColdFusion or ASP or PHP.

E-commerce Use of Internet technology to perform legally binding commercial and / or financial transactions.
The best-known examples are selling / buying things on the web and web banking.

Extranet System which uses Internet technology (browsers, etc.) to provide information and applications only to members of one organisation plus tightly-controlled outsiders.
For example a large company may enable / require its suppliers to connect to its extranet in order to streamline its purchasing.

FAQ Frequently Asked Questions.
Many sites use lists of answers to Frequently Asked Questions to minimise the number of phone and email queries visitors raise. This benefits both the site and their visitors.

Frames Technique for making a web page behave like several independent pages on the same screen. Useful for things like:

Adding an index ("navigation bar") to the rest of the page or the rest of the web site.
Instructions or explanations which the user can scroll through without losing his / her place in the rest of the page.
Benefit from IT's website uses frames for both of these purposes - this Dictionary is an example!

FTP File Transfer Protocol, the technique for transferring files in either direction between a web site and the user's computer.

HTML Hypertext Mark-up Language, the language used by websites to tell browsers what information to display and how to format it.

HTTP Hyper-Text Transfer Protocol, the technique for delivering web pages to your browser.

Hyper-Text Text which contains links to just about anything the developer thinks will be useful to the user, in the same or separate files / documents.
The use of hyper-text is not restricted to web pages, for example the help facilities in most Windows software use hyper-text links.
Links can refer to many other things besides text, for example web pages can contain links to graphics, sounds and even computer programs.

Intranet System which uses Internet technology (browsers, etc.) to provide information and applications only to members of one organisation.

ISP Internet Service Provider, an organisation which operates one or more computer systems which its customers use for e-mail and for their websites.

Java Language frequently used to write applets (see note on "Applet").

JavaScript Mini-language used to write routines which are downloaded into a browser to facilitate the dialogue between a user (via the browser) and a website. JavaScript functions cannot cause damage because they cannot create / access / modify / delete files (except cookies) on the user's computer. But many users prevent their browsers from running JavaScript functions because they do not understand the limitations which make JavaScript safe.

Jscript Microsoft's version of JavaScript. See the note on JavaScript.

LAN Local Area Network, a network connecting computers in a small area (usually in the same building).

Navigation bar Block of text or graphics which contains links to the rest of the page and / or to the rest of the web site and / or to other websites.

Operating system Complex software which manages a computer system and provides services to applications.
For example an application does not itself display or print information or read / write files, it asks the operating system to do these things for it.

PHP A system which provides:

A programming language which can be used to produce dynamic web pages.
An application server program (see "server") which runs programs written in the PHP language.

Plug-in Program which a browser uses to help do something it can't do on its own, e.g. play sounds or movies.
Users may refuse to accept plug-ins because they are written in full-strength programming languages and therefore by mischief or accident can cause serious damage to files on users' PCs.
See the notes on "Active X control" and "Applet".

Pop-up page Additional web page opened in a separate window.
This can often be useful, e.g. to present "help" information, definitions of words / phrases or terms of business.
Unfortunately some commercial sites make a nuisance of pop-up windows to force users to look at advertisements, etc.

Rollover In a web page this usually refers to changing the content of an image, either when the user clicks / moves the mouse over it or when a program issues certain instructions.
Our "Office Assistant" demo uses a lot of rollovers controlled by a Javascript program, and its "Autorewind On / Off" button changes its content when you click it. The "Drop-down Menu" demo shows menu items changing colour when you move the mouse over them.

Search engine Web site which helps you find web sites about subjects you specify. A typical search engine offers a text box in which you type keywords which define what you want. When you click the button beside the text box, the search engine displays links to the sites it's aware of which feature these keywords.

Server

A computer which provides services to another. The best-known example is probably the servers used by websites and ISPs to store and display web pages.
Software which provides services to other programs. Different server programs which collaborate may run on the same or different computers.

Shopping cart E-commerce application which displays the goods / services in a firm's catalogue, keeps track of the list of items the visitor has chosen and enables the visitor to pay for these items.

Spam Junk e-mail. Spammers use programs which extract e-mail addresses from web pages to compile their mailing lists. Fortunately there's a fairly simple way to make life difficult for these programs, and we use it.

Tooltip Little box which pops up to tell the user what some part of a web page or an application screen does or is about. It usually has small black letters on a yellow background.

URL Universal Resource Locator, the identifier / address of an object which may be accessed via the Internet.
There are several types of accessible objects but the best-known are Web pages and e-mail addresses.

VBScript A Microsoft language which performs the same functions as JavaScript. See the note on JavaScript.

Visual Basic A Windows programming language often used to develop applications which run on PCs and LANs / WANs because it offers a good balance of ease of use, wide range of features and extendability.

WAN Wide Area Network, a network connecting computers which are separated by a significant distance.


Active X control	Screen item (e.g. a scrollable grid for allowing multi-line data entry) downloaded from a website into a browser and run from the browser on the user's PC. Users may refuse to accept Active X controls because they are written in full-strength programming languages and therefore by mischief or accident can cause serious damage to files on users' PCs. See the notes on "Applet" and "Plug-in".
Applet	Miniature application program downloaded from a website into a browser and run from the browser on the user's PC. Users may refuse to accept applets because they are written in full-strength programming languages and therefore by mischief or accident can cause serious damage to files on users' PCs. See the notes on "Active X control" and "Plug-in".
ASP	Active Server Pages, a system which provides: A programming language which can be used to produce dynamic web pages. An application server program (see "server") which runs programs written in the ASP language.

Bookmark	Make your browser save the URL and title of a web page so you can easily find it again.
Browser	Program which presents information from any website (chosen by the user) - usually runs on a PC. There are dozens of browser programs but a recent survey concluded that: the vast majority of users use Microsoft's Internet Explorer on some version of Windows almost all the rest use Netscape's Navigator / Communicator on some version of Windows.

C++	Programming language which is used for writing operating systems, high-speed games and other programs which need speed and / or the ability to use all the facilities of the operating system. Too complex to be an economical tool for developing most commercial and administrative systems - Visual Basic and a number of other languages are generally better for this.
Chromeless window	A browser window which has none of: Toolbar - so no Back and Forward buttons. Menu bar. Address / location bar. Status bar. so the user has almost no control over what happens. Usually a very bad design technique.
ColdFusion	A system which provides: A programming language which can be used to produce dynamic web pages. An application server program (see "server") which runs programs written in the ColdFusion language.
Cookie	A file stored on a PC by the browser and sent to the relevant web site with each page request. Often used by websites to maintain details of the user from one session to another. Sometimes used to make life easier for the user, too often used to push advertising at the user. Some users set their browsers to prevent websites from storing cookies.

Data model	The first stage of database design. It's important to get this right because errors are likely to mean that: You won't be able to store, retrieve and cross-refer data in the way you need. If you change the database structure to remedy these problems, you'll also have to change all programs which read or update the changed part of the database and perhaps others which implicitly assume that the database is structured in the old way.
Default page (of a website)	The page which is displayed if the visitor does not specify a page. The name depends on how the website is set up but is most commonly "index.htm" If there is no default page or the website does not recognise a page which is present as being the default page, visitors see a directory listing rather like Windows Explorer's - not usually desirable, especially if you want visitors to register or to provide a user id and password before they can see the rest of the site.
DHTML	Dynamic HTML, an extension of HTML which allows the page to vary what it shows and how it behaves in a limited way depending on the circumstances. We say "limited" because if a page is built using only DHTML the underlying content of the page is always the same so it will always display the same set of contents and behaviours - see the note on "Dynamic web pages".
Domain	The part of a URL which identifies the site, for example in www.mywebsite/mypage.htm "mywebsite" is the domain name. There's been a mad scramble for attractive domain names in recent years and it's getting increasingly difficult to find one which is not already taken and not too similar to one which is already taken.
Dynamic web pages	Pages whose whole content varies depending on the circumstances, usually on the results of searches in a database. Dynamic web pages are an essential part of e-commerce applications, e.g. to display the goods / services in a firm's catalogue, to keep track of the list of items the visitor has chosen and to enable the visitor to pay for these items. It's very difficult to build dynamic web pages without using a tool such as ColdFusion or ASP or PHP.

E-commerce	Use of Internet technology to perform legally binding commercial and / or financial transactions. The best-known examples are selling / buying things on the web and web banking.
Extranet	System which uses Internet technology (browsers, etc.) to provide information and applications only to members of one organisation plus tightly-controlled outsiders. For example a large company may enable / require its suppliers to connect to its extranet in order to streamline its purchasing.

FAQ	Frequently Asked Questions. Many sites use lists of answers to Frequently Asked Questions to minimise the number of phone and email queries visitors raise. This benefits both the site and their visitors.
Frames	Technique for making a web page behave like several independent pages on the same screen. Useful for things like: Adding an index ("navigation bar") to the rest of the page or the rest of the web site. Instructions or explanations which the user can scroll through without losing his / her place in the rest of the page. Benefit from IT's website uses frames for both of these purposes - this Dictionary is an example!
FTP	File Transfer Protocol, the technique for transferring files in either direction between a web site and the user's computer.

HTML	Hypertext Mark-up Language, the language used by websites to tell browsers what information to display and how to format it.
HTTP	Hyper-Text Transfer Protocol, the technique for delivering web pages to your browser.
Hyper-Text	Text which contains links to just about anything the developer thinks will be useful to the user, in the same or separate files / documents. The use of hyper-text is not restricted to web pages, for example the help facilities in most Windows software use hyper-text links. Links can refer to many other things besides text, for example web pages can contain links to graphics, sounds and even computer programs.

Intranet	System which uses Internet technology (browsers, etc.) to provide information and applications only to members of one organisation.
ISP	Internet Service Provider, an organisation which operates one or more computer systems which its customers use for e-mail and for their websites.

Java	Language frequently used to write applets (see note on "Applet").
JavaScript	Mini-language used to write routines which are downloaded into a browser to facilitate the dialogue between a user (via the browser) and a website. JavaScript functions cannot cause damage because they cannot create / access / modify / delete files (except cookies) on the user's computer. But many users prevent their browsers from running JavaScript functions because they do not understand the limitations which make JavaScript safe.
Jscript	Microsoft's version of JavaScript. See the note on JavaScript.

LAN	Local Area Network, a network connecting computers in a small area (usually in the same building).

Navigation bar	Block of text or graphics which contains links to the rest of the page and / or to the rest of the web site and / or to other websites.

Operating system	Complex software which manages a computer system and provides services to applications. For example an application does not itself display or print information or read / write files, it asks the operating system to do these things for it.

PHP	A system which provides: A programming language which can be used to produce dynamic web pages. An application server program (see "server") which runs programs written in the PHP language.
Plug-in	Program which a browser uses to help do something it can't do on its own, e.g. play sounds or movies. Users may refuse to accept plug-ins because they are written in full-strength programming languages and therefore by mischief or accident can cause serious damage to files on users' PCs. See the notes on "Active X control" and "Applet".
Pop-up page	Additional web page opened in a separate window. This can often be useful, e.g. to present "help" information, definitions of words / phrases or terms of business. Unfortunately some commercial sites make a nuisance of pop-up windows to force users to look at advertisements, etc.

Rollover	In a web page this usually refers to changing the content of an image, either when the user clicks / moves the mouse over it or when a program issues certain instructions. Our "Office Assistant" demo uses a lot of rollovers controlled by a Javascript program, and its "Autorewind On / Off" button changes its content when you click it. The "Drop-down Menu" demo shows menu items changing colour when you move the mouse over them.

Search engine	Web site which helps you find web sites about subjects you specify. A typical search engine offers a text box in which you type keywords which define what you want. When you click the button beside the text box, the search engine displays links to the sites it's aware of which feature these keywords.
Server	A computer which provides services to another. The best-known example is probably the servers used by websites and ISPs to store and display web pages. Software which provides services to other programs. Different server programs which collaborate may run on the same or different computers.
Shopping cart	E-commerce application which displays the goods / services in a firm's catalogue, keeps track of the list of items the visitor has chosen and enables the visitor to pay for these items.
Spam	Junk e-mail. Spammers use programs which extract e-mail addresses from web pages to compile their mailing lists. Fortunately there's a fairly simple way to make life difficult for these programs, and we use it.

Tooltip	Little box which pops up to tell the user what some part of a web page or an application screen does or is about. It usually has small black letters on a yellow background.

URL	Universal Resource Locator, the identifier / address of an object which may be accessed via the Internet. There are several types of accessible objects but the best-known are Web pages and e-mail addresses.

VBScript	A Microsoft language which performs the same functions as JavaScript. See the note on JavaScript.
Visual Basic	A Windows programming language often used to develop applications which run on PCs and LANs / WANs because it offers a good balance of ease of use, wide range of features and extendability.

WAN	Wide Area Network, a network connecting computers which are separated by a significant distance.