Glossary of web terms

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

A

Adobe Acrobat Files
Files saved in a postcript format from Adobe Acrobat software, otherwise known as Portable Document Formats (PDF). These files can be read with free Adobe Acrobat Reader software available from http://www.adobe.com/

ALT Tag
The alt tag is a text description of an image (alt being short for alternative text). The text description appears when the mouse is rolled over an image on a web page. It is most helpful for people who view pages in text-only mode or have slow connections or for those with visual impairments, who use screen readers to access web pages.

Anchors
Anchors are used to mark specific loations within a document. Once an anchor is placed in a location, you can create a link to that spot. They are also often referred to as bookmarks. The term Anchor also relates to standard links from one page to another - these links are marked by an Anchor Tag or A tag.

Animated GIF
An image file that appears to provide motion through the use of multiple images displayed sequentially.

Applets
Small programes or applications written in Java.

ASP (Active Server Pages)
An Active Server Page is a web page that includes program code that is processed on a Microsoft web server before the page is sent to the user. The code is typically used to access data from a database and that data is then built into the returned web page "on the fly".

ASP was developed by Microsoft and is a feature of Microsoft's web server software, but the dynamically generated pages can be viewed by almost any browser. The ASP program code is usually written in Visual Basic Script or Java Script.

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B

Bandwidth
Commonly referred to as the amount of data that can be transferred over a network connection. Bandwidth is normally measured in megabits per second (Mbps). Simple HTML web pages do not require a large amount of bandwidth but full motion video will be viewed better on higher bandwidth.

Base URL
Sets the URL for which all links in the web page are based.

Bookmark
A record kept by web browers of selected web sites. The user can return directly to a particular site by accessing their bookmark file. The term bookmark can also be used in reference to Anchors.

Browser
A browser, or web browser, is the software used to view web pages and interact with various kinds of Internet resources. The browser interprets the HTML used to format web documents and recreates the page on your screen. There are a variety of web browsers available, the two most common being Microsoft's Internet Explorer and Netscape's Navigator.

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C

Cache
A cache is temporary memory designed to speed up access to resources. Previously accessed web pages are stored on the disk of the personal computer running the browser. When a user is flipping back and forth between previously accessed pages, the browser retrieves the pages from the local disk rather than from the remote server. Use of cache speeds up retrieval, reduces network traffic and decreases load on the server.

Cache memory can be set up for a group of users - e.g. an organisation, a region, a country, on a Proxy Server. Requests for web pages are routed first to a proxy server, which keeps a copy of pages it has retrieved. When any browser requests a page, the proxy server will return the page if it is already in its memory rather than retrieve it from the original host server.

Cascading Style Sheets (CSS)
A Cascading Style Sheet (CSS) provides the ability to separate the layout and styles of a web page from the data or information. Styles such as fonts, font sizes, margins, can be specified in one place, then the Web pages feed off this one master list, with the styles cascading throughout the page or an entire site.

CGI Scripts (Common Gateway Interface)
CGI scripts are the most common way for a web server to pass a user's request to an application or program. CGI scripts are used for tasks such as submitting forms to a web server. Having completed an online web form, the form is submitted to the web server and then the data from the form will be processed by the CGI script. The script may send back a confirmation message telling the user that the form has been submitted successfully or unsuccessfully.

Cookie
A cookie is a small piece of data which is sent from a web server to a web browser and stored locally on the user's machine. The cookie is stored on the user's machine but is not an executable program and cannot do anything to the machine. Whenever a web browser requests a file from the same web server that sent the cookie, the browser sends a copy of that cookie back to the server. In this way, the server knows that it has visited before and can co-ordinate access to different pages on its website. For example, Internet shopping sites use cookies to keep track of which shopping basket belongs to which user. Cookies are also commonly used in order to personalise web pages. (Amazon - "Welcome Janet Stam, we have some recommended titles for you.")

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D

DNS (Domain Name Server)
This is a server that matches up the URL of a website (e.g. www.liv.ac.uk) with its proper numeric IP address - it translates www.liv.ac.uk into the unique numeric IP address (138.253.31.2). Whenever you request a web page the web browser must consult the domain name server to find out what the numeric translation of the URL is. This is necessary because computers only understand the numeric IP address, whereas we humans prefer to use meaningful and more memorable text.

Domain
The domain is the part of a web address that specifies what the organisation is and where the computer is located. For example:

• .ac.uk - Academic institution in the UK
• .gov.uk - Government organisation in the UK
• .co.uk - Commercial company in the UK
• .edu - Academic institution in the USA

Domain Name
This is the name registered by an organisation with the Name authorities that is then associated with a specific Internet address e.g. www.liv.ac.uk or www.amazon.co.uk.

Domain names have to be registered to be valid and usable on the Internet. It can take a number of days before a new domain name becomes active. All Internet providers must update their DNS tables to record a new sites location.

* If you are considering registering a domain name for a site hosted on the University web server please contact the Webteam.

DHTML (Dynamic Hypertext Markup Language)
DHTML is the marketing term applied to a mixture of standards, including HTML, Cascading Stylesheets, scripting.

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E

F

FAQ (Frequently Asked Questions)
FAQs are widely used on the Internet and usually provide a good mechanism of gaining an overview on a topic.

Firewall
As the term conveys, a firewall is an extra layer of security built into computers on a network, which restricts access to systems from the outside world. Firewalls protect against hackers and malicious intruders.

Flash
Flash is an animation format developed by the company Macromedia. One reason for the popularity of Flash is the file sizes are small. Animated, interactive content can be quickly downloaded. However, to be able to view a Flash file the user requires the Flash plug-in.

Frames
Frames is the use of multiple, independently controllable sections on a web page.

Freeware
Software on the web that is freely available (but retains a copyright).

FTP (File Transfer Protocol)
A method of transferring files from one computer to another. FTP is the most widely used way of downloading and uploading (getting and putting) files across an Internet connection. FTP software (WS_FTP on MNTS & W2KS) can be used to upload web pages that you have created and saved on your desktop PC to the University web server.

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G

H

Hit
A hit is a single file request in the access log of a web server. A request for an HTML page with three images will result in four hits in the log: one for the HTML file and one for each of the graphic image files. Whilst hits can give a meaningful measure of how much traffic a web server is processing, a better way of understanding accesses to a website is to look at the number of pages accessed (e.g. just html files).

Home Page
A homepage is the first, introductory page of a web site, from which other pages in the site can be accessed.

HTML (Hypertext Markup Language)
The standard publishing language for pages on the World Wide Web. A web browser interprets the HTML used to format web documents and then displays the document on the screen. Specifications for standard HTML and other web publishing languages are developed by an international body, the World Wide Web Consortium (W3C).

HTTP (Hypertext Transfer Protocol)
A protocol or language used to request and transfer web pages across the Internet.

Hypertext links
The ability to link from one document to another relevant document. Links can be embedded in text or graphics on web pages.

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I

Image Map
An image map is an image with clickable regions within it (example: see the University's interactive campus map). There are two types of image maps: client side, which contain co-ordinate information within the graphic file, and server side, which contains its co-ordinate information in a separate file on the server.

Information Architecture
Term used to describe the organisation of information, the content, functionality, navigation and usability of a web site.

Internet
The vast collection of inter-connected networks across the world that all use the TCP/IP protocols.

Intranet
A private network within an organisation. An Intranet uses regular Internet protocols and in general tends to appear as a private version of the Internet.

IP Address/IP Number
The unique address of a computer in a network. IP addresses follow a specific structure, e.g. 138.255.60.59, and are used to identify each sender or receiver of data sent across the Internet. IP addresses can be likened to a telephone number - when you "call" that number, you are connected to the computer that "owns" that IP address.

IRC (Internet Relay Chat)
A text-based conference system that allows users to communicate synchronously. Users log into a channel on which other users are "chatting" and the conversations are displayed on the screen.

ISP (Internet Service Provider)
An ISP is a company that provides access to the Internet to individuals or companies. ISPs provide local dial-up access from your personal computer to their computer network and their network connects you to the Internet.

ISDN (Integrated Services Digital Network)
Allows users to send digital information at 128kb. Works no differently to a normal telephone line - just digital and faster.

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J

Java
Java is a programming language created by Sun Microsystems expressly designed for the Internet environment. It is similar to C++, but simpler to use. Java can be used to create complete applications, or to build small application modules, known as applets, for use as part of a web page. Applets enable greater interactivity on web pages, for example, diary or booking applications.

JavaScript
JavaScript is a script language - a system of programming codes, created by Netscape, that can be embedded into the HTML of a web page to add functionality. JavaScript should not be confused with the Java programming language. In general, script languages such as JavaScript are easier and faster to code than more structured languages such as Java and C++. Examples of JavaScript use in web site development:

• Automatically change a formatted date on a Web page.
• Cause an additional pop-up window to appear.
• Cause text or images to change when the mouse pointer rolls over.

K

L

LAN (Local Area Network)
The system for networking a group of computers at the same physical location.

Link
The address of another document embedded into a Web page, so that if you click on the associated text or button, you retrieve the linked document.

Link "Rot"
Term used to describe the frustrating and frequent problem of dead-end links - e.g. you click on a link on a web page but then get an error message due to documents having been moved, web sites being reorganised or discontinued.

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M

Metadata or Meta tags
An electronic document's metadata is simply information about that document, which is used by Internet search engines to find and classify websites. Typically, metadata tags are embedded into the HTML of a web page (in the 'head' section). This metadata is not seen by users when viewing a web page unless they choose to look at the underlying source code.

MPEG (Motion Picture Exports Group)
A method of video file compression.

N

• Navigation bars - a collection of links to the most important pages of a website.
• Site maps - provide a global view of the organisation of a website.
• Alpha bars - an alphabetical list (A to Z) that links into a document that is structured alphabetically, e.g. an index. (This page uses alpha bars.)

Netscape
Company that developed the Netscape Navigater web browser, for viewing web pages.

Network
A number of computers linked together.

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O

P

PDF (Portable Document Format)
Files saved in a postcript format from Adobe Acrobat software, otherwise known as Portable Document Formats (PDF). These files can be read with free Adobe Acrobat Reader software available from http://www.adobe.com/.

Pixel
Tiny squares of colour, arranged in rows and columns and which together produce an image on a computer screen. Everything you see on your monitor is displayed using pixels. It's the on-screen equivalent of a dot on a piece of paper.

Plug-in
Additional software, which works in conjunction with web browsers to enhance their capabilities, such as in playing audio or video (e.g. RealPlayer) or animated graphics (Flash or Shockwave). The most common plug-ins are available free for downloading over the Internet.

Protocol
The 'language' spoken between computers to help them exchange information. More technically, it is a formal description of message formats and the rules that two computers must follow in order to exchange those messages.

Proxy Server
A proxy server is an intermediary between the user's computer and the computer they wish to access. For example, if a user browsing the web requests a page from a web server at a university in the USA, the request is directed to the proxy server, which then makes the request from the USA Web server. A proxy server has the role of a cache memory and is frequently used within firewalls.

Publish Web Pages
To "publish" web pages is used to describe the uploading of web pages onto the web server, thus making them available to others across the Internet.

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Q

R

Relative Font Sizes
It is recommended that you use relative font sizes in order to ensure maximum accessibility for your web pages. A relative font size is where the font size is specified in HTML code as +1, +2,... or -1, -2... This means that the font size will be displayed through the users browser as +1 or -1 in relation to the browser's default font settings. It also means that the user can increase or decrease the display of the font through their web browser settings. If fixed font sizes are used some users may not be able to override these settings and therefore have difficulty accessing the content.

Rollover
An action or event takes place when the cursor passes over a specific image or section of text on a web page.

S

Screen Reader
A software programme that reads the contents of the screen aloud to a user. Screen readers are primarily used by individuals with visual impairments.

Search Engine
Internet search engines (e.g. Google, AltaVista) help users find web pages on a given subject. The search engines maintain databases of web sites and use programs (often referred to as "spiders" or "robots") to collect information, which is then indexed by the search engine. Similar services are provided by "directories," which maintain ordered lists of websites, e.g. Yahoo!

Server
A high-power computer that is used to store and distribute data and/or applications.

SSI (Server Side Includes)
Web technology that instructs a web server what to include in a dynamically generated Web page by inserting code into a template web page.

SHTML
Usually seen as .shtml. A file name extension that identifies web pages containing Server-side Includes.

SSL (Secure Sockets Layer)
A web technology that provides security for web transactions by handling authentication, data enryption and digital signatures. Most e-commerce web sites use SSL to process payment transactions.

Splash Page
This term is used to describe a welcome page sometimes be found on web sites. Splash pages are intended to entice the visitor into a site and often use Flash and graphic animation. A splash page can, however, cause problems for search engines trying to access your web site to index it.

Spiders
Spiders are programmes used by search engines to visit web sites and collect the data for the search engine to index. Spiders are also referred to as "robots" or "bots."

Statistics
See: Usage Statistics.

Streaming
This term is used to describe video or audio files which are compressed when sent over the Internet and displayed by a viewer (e.g. RealPlayer) as they arrive. These files are more user-friendly and efficient than standard file formats, which require the entire file to download before a user can access or view the file.

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T

TCP/IP (Transmission Control Protocol/Internet Protocol)
TCP/IP is the standard communications protocol (language) required for computers on the Internet.

Thumbnails
Small versions of larger graphics, which are usually used on web pages as a link to the larger graphic version.

U

UNIX
UNIX is a multiuser, multitasking operating system. The main University web server (pages starting with the URL http://www.liv.ac.uk/ are on the main University web server) uses the UNIX operating system.

URL (Uniform Resource Locator)
A URL is the unique address of a web document, eg: http://www.liv.ac.uk/webteam/glossary/index.htm.

Upload
To transfer a file from a desktop computer onto a web server.

Usage Statistics
Statistics that show how a website is being used. Statistics often indicate the busiest times of a web site, which pages are accessed most, which web browser software visitors are using.

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V

Validator
An automated tool to check that coding used to create web pages is valid. It is important that coding is valid as this can impact on the accessibility of pages. Assistive technology used by disabled users such as screen readers may have problems if coding is invalid. Search engines may also have difficulty indexing pages. Most web editing packages include HTML validators or checkers, alongside spell checkers. Online validators are also available, e.g. W3C HTML validator and Style Sheet Validator.

Version Control
A system of indicating and recording the particular edition (or version) of a web page.

W

WAI (Web Accessibility Initiative)
Guidelines put in place to highlight and improve the difficulties experienced by many web users. The guidelines can be accessed at http://www.w3.org/TR/WAI-WEBCONTENT/

Webcast
The delivery of live or delayed sound or video broadcasts using web technologies. The sound or video is captured by conventional video or audio systems. It is then digitised and streamed on a web server.

Web Page
A document or file, written in HTML, that is stored on a web server and can be viewed over the Internet using an web browser.

Webmaster
Administrator, maintainer and/or creater of a web site.

Web server
See: Server.

Web Site
A collection of connected web pages stored on a web server.

WWW (World Wide Web)
The "World Wide Web" is a collection of online documents stored on servers around the world, that are connected to the Internet. The concept of the web was created by researchers at CERN in Switzerland. Web documents are written in HTML and stored on a web server. The documents can be accessed over the Internet using a web browser, such as Internet Explorer or Netscape Navigator. When these browers access a page, they send a request to the web server which then sends the requested document back to the web browser, using the Hypertext Transfer Protocol (http).

W3C (World Wide Web Consortium)
The W3C is the international standards body. It was established in 1994 to lead the web to its full potential by developing common standards. Website: http://www.w3c.org/.

WYSIWYG
An acronym for What You See Is What You Get. WYSIWYG is used to describe applications that let you see how a finished HTML document will look whilst still letting you edit it. Dreamweaver and FrontPage are two WYSIWYG HTML editors.

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X

XHTML (eXtensible Hypertext Markup Language)
XHTML is the next generation of HTML and is a hybrid between HTML and XML. XML was designed to describe data. HTML was designed to display data. XHTML is much stricter than HTML. Not all browers support XML so XHTML provides an intermediary soluton and can be interpreted by XML and HTML browsers.
For further information see: http://www.w3c.org/MarkUp/.

XML (eXtensible Markup Language)
XML is an emerging format to structure, store and send information. XML allows the author to define their own tags and their own document structure. XML is not a replacement for HTML. In future web developments it is likely that XML will be used to describe and transfer data and HTML used to format and display the same data. XML can be seen as a cross-platform, independent tool for exchanging data.
For further information see: http://www.w3c.org/XML/.

Y

Z

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