HTML Glossary

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ADPCM: A compression technique for sound files.
AIFF: A popular Mac format for sound files.
Anchor: The anchor tag (<A>) is used to define both anchors and links. An anchor is a named place in a document that other documents can form a link to.
ANSI: American National Standards Institute, an organization that sets many standards for the computer industry.
ASCII: American Standard Code for Information Interchange, the mapping of ordinary letters and numbers to standard numerical representations. Often used to refer to plain text that does not contain word-processing codes.
Attribute: A setting for a tag, that affects the way the tag is displayed.
AU: A popular Unix format for sound files.
AVI: Audio Video Interleave, a popular format for video files.
Bandwidth: The share of a communications link occupied by a particular transfer. Large image or sound files consume a lot of bandwidth.
BMP: Bitmap, a popular Windows format for image files.
Boolean: Refers to something that can be True or False. A checkbox is a good way for a form to get a true or false answer from a user.
Browser: A program used to access and display web pages. Graphical browsers can display images and many different text fonts; non-graphical browsers cannot.
CGI: Common Gateway Interface, a way to allow users to provide information to scripts attached to web pages, usually through forms
. For more information see the CGI 1.1 standard documentation.
Cyberspace: The imaginary space users of the web move around in. A metaphor that many people take almost literally.
Decimal Point alignment: A form of alignment for columns of numbers so that all of the decimal points line up under each other.
Domain Name: The name of an Internet site, for example www.nortel.com or www.willcam.com.
en Space: A space as wide as half the current point size (typically as wide as the letter n in many fonts.) The related em space is as wide as the current point size (as wide as m in many fonts.) The en dash is a dash as wide as an en space, and an em dash is a dash as wide as an em space. A no break space is as wide as a regular space, but browsers will not break the line at a no break space even if they would at a regular space.
Entity: A special character such as & that needs to be entered with an escape sequence. An iconic entity is a small icon that is useful in lists and headings, such as a folder icon to represent a directory. Lists are available of iconic, character, and mathematical entities.
Fixed Width Text: Also called monospaced text, fixed width text is set in a font in which every character occupies the same width. In contrh[Tast, proportional width fonts use more space for a w or m than an i or l. Many authors used fixed width fonts to indicate material a user should type letter-for-letter.
Font: A font, strictly speaking, is a set of characters that all belong to the same size and style of a typeface. For example, Courier is a typeface, and 11 point italic Courier is a font; 12 point bold Courier is a different font. In practice most people use the word font to mean typeface, saying that Courier is a font.
Forms: The mechanism by which web pages become interactive, allowing users to supply input to CGI scripts.
FTP: File Transfer Protocol, a way to exchange files with other sites on the Internet.
GIF: Graphics Interchange Format, a popular Windows format for image files.
Gopher: A protocol that is older than HTTP and serves a similar purpose, allowing users to tunnel through cyberspace in search of information.
Graphic: A picture or illustration, also called image. Formats include GIF, JPEG, BMP, PCX, and TIFF.
HTML: HyperText Markup Language, the language in which web pages are written.
HTTP: HyperText Transfer Protocol, the conventions used by web browsers and servers to transfer web pages.
Hypermedia: A combination of hypertext and multimedia that allows users to move in a non-linear fashion through text, images, sounds, and other information.
Hypertext: A collection of documents joined by links so that users can read it in a variety of different orders.
Icon: A small graphic that can be used as a bullet character or mixed with text.
IETF: Internet Engineering Task Force, the volunteer group that defines most Internet standards.
Image: A picture or illustration, also called graphic. Formats include GIF, JPEG, BMP, PCX, and TIFF. An inline image is mixed with text and displayed surrounded by text.
Image File: A file containing an image.
Image Map: An image with a number of different links associated with it. Clicks on different portions of the image go to different links. All browsers that can display images support server-side image maps; newer browsers also support client-side image maps, which resolve more quickly and can provide more feedback to the user.
Indented: Text whose left margin is to the right of the usual text margin.
Indexers: Programs that read pages throughout the web and add a description of their contents to a database that can be searched by users looking for specific information.
ISO: International Standards Association, an organization that sets standards used around the world, such as standard two letter abbreviations for country names.
JPEG: Joint Photographic Experts Group, a popular cross-platform format for image files.
LaTeX: A series of macros for the text description language TeX, used to create sophisticated typesetting effects. It is especially well suited to equations, formulas, and long academic papers with many footnotes and references and is generally available on Unix systems. The MATH element of HTML draws heavily on LaTeX. There are a number of FAQs available on TeX and LaTeX.
Link: The anchor tag (<A>) is used to define both anchors and links. A link is a directive to a browser: when a user selects a link a new page is loaded. Some people call a link a hotlink or hyperlink. An external link leads to a page other than the current one; an internal link leads elsewhere on the current page. Some people refer to relative and absolute links; these adjectives are more properly applied to a URL.
Literal: Characters that should be displayed as they were typed, without any translation of codes.
Media Type: As explained in RFC 1590, what used to be called "MIME types" or "Mime Content Types" are now called "Media Types." They define the content of a file or attachment: for example the media type "video/mpeg" indicates that a file is an MPEG video. The type "text/html; version=3.0" indicates that a file contains HTML source that relies on HTML 3.0 -- files for HTML 2.0 have a media type of "text/html" with no version number.
MIDI: Musical Instrument Digital Interface, a popular cross-platform format for sound files.
MIME Content Type: A description of the contents of a file or attachment, now called Media Type.
Mnemonic: A series of letters designed to aid the remembrance of a code or sequence. For example amp is a mnemonic for "ampersand", the & symbol.
MPEG: Moving Pictures Expert Group, a popular cross-platform format for sound and video files.
Multimedia: The combination of several different communications techniques: for example sound, written text, still pictures, and moving pictures.
Nested: An element that is entirely contained within another element. For example, the phrase "the quick brown fox" contains a bold element (the word "quick") nested within an italic element (the entire phrase.) Some browsers will display the word "quick" only as bold, others will display it as both bold and italic.
Netscape Extensions: A group of extra features that are supported by the Netscape browser. These features are not part of HTML 2.0 or 3.0 and are not usually supported by other browsers.
PCX: A popular Windows format for image files.
Pixel: The smallest area that can be displayed on a given screen. Each pixel can be a different colour. Screen resolutions are expressed in pixels, for example 800 pixels by 600 pixels.
Player: An application used to display an sound or video format not supported by a particular browser. One of the many helper applications browsers such as Netscape use to support a variety of formats.
Point: A unit of font size.
Pop-Up Window: A small window that pops up over the one being displayed, to show a definition or footnote, then disappears.
Render: To render a page is to translate the codes and directives, embed any inline images, and highlight links and other special areas.
Server: A program running on an Internet site that makes the web pages at that site available to browsers throughout the Internet.
SGML: Standard Generalized Markup Language. HTML is a derivative of SGML.
Site: Some people use the word site to refer to an Internet site, which has a domain name, while others refer to a web site, a collection of web pages joined byh[T links and all located at the same Internet site.
SND: An extension used for a variety of different sound file formats.
Sound: Popular sound file formats include AU, WAV, SND, MPEG, MIDI, AIFF, ADPCM
Tags: Tags are used to define elements in HTML. Most tags have both a start tag, such as <LI> and a corresponding end tag, such as</LI>. Typographic tags like <B> for "bold" or <I> for "italic" describe the appearance of the text; idiomatic tags like <EM> for "emphasize" or <STRONG> for "strongly emphasize" describe the reason for the appearance change. Different browsers may choose different appearances for the same idiomatic tag.
TIFF: Tagged Image File Format, a popular Mac format for image files.
UNIX: An operating system that many computers on the Internet, including many web servers use.
URL: Uniform Resource Locator, a description of the location of a link or image file. It specifies the protocol (http:// for a web page,) site name, path and file name to the resource.
Viewer: An application used to display an image format not supported by a particular browser. One of the many helper applications browsers such as Netscape use to support a variety of formats.
Video: A moving picture, accompanied by sound.
VRML: Virtual Reality Markup Language, a way to describe "worlds" that are displayed in three dimensions for the user to "walk through" or "fly over." For more information, see the VRML FAQ.
W3: The name of the consortium that is steering standards development for the World Wide Web.
WAV: A popular Windows format for sound files.
Whitespace: A character that leaves some empty space on the screen: a space, tab, or carriage-return.
WYSIWYG: What You See Is What You Get. A feature sorely lacking in HTML editors.

dows format for image files.

The smallest area that can be displayed on a given screen. Each pixel can be a different colour. Screen resolutions are expressed in pixels, for example 800 pixels by 600 pixels.

Player

An application used to display an sound or video format not supported by a particular browser. One of the many helper applications browsers such as Netscape use to support a variety of formats.

Point

A unit of font size.

Pop-Up Window

A small window that pops up over the one being displayed, to show a definition or footnote, then disappears.

Render

To render a page is to translate the codes and directives, embed any inline images, and highlight links and other special areas.

Server

A program running on an Internet site that makes the web pages at that site available to browsers throughout the Internet.

SGML

Standard Generalized Markup Language. HTML is a derivative of SGML.

Site

Some people use the word site to refer to an Internet site, which has a domain name, while others refer to a web site, a collection of web pages joined byh[T