a set of codes that can be inserted into text files to indicate special typefaces, inserted images, and links to other hypertext documents.

The main use ofHTMLis to publish information on the Internet (see World Wide Web ). Here is a simple example of an HTML document.

Figure 132 shows how this looks when displayed by a web browser. HTMLfeatures are indicated by special codes, called tags. If there were an HTML tag called XXX, then the characters <XXX> would mark the beginning of this feature, and </XXX> would mark the end. For example, the keywords <TITLE> and </TITLE> mark the beginning and end of the title. <P> marks a paragraph break, and <IMG SRC=filename>embeds an image in the document; many image formats are supported but GIF is the most popular. Codes for special typefaces include the following:

The tag <BR> inserts a line break; note that the line breaks on the displayed web page will not necessarily match the line breaks on the original HTML text. The tag <HR> inserts a horizontal rule.

An unnumbered list of items can be inserted as follows:

An ordered (numbered) list is created in the same manner, except with <OL> used in place of <UL>.

A link to another document looks like this:
<A HREF="XXXX.HTML"> Click here.</A>
That means "Jump to file XXXX.HTML (another HTML document) if the user clicks on the words 'Click here.'" A URL can appear in place of the filename. A link to another place in the same document looks like this:
<A HREF="#XXXX">
This is the text that will display the link</A>
When the user clicks on this link, the browser will jump to the location in the current document marked with
<A NAME="XXXX"> This is the target of the link</A>
Comments (to be ignored by the HTML system) look like this:
<! This is a comment>

Even with no special codes in it, a text file is still a valid HTML document.

Although you can use almost any word processor or page layout program to produce HTML, it is much easier to use a program specially designed for the job (Adobe PageMill, Corel Xara, Microsoft FrontPage, and other "web publishers"). Many of the newer programs provide a WYSIWYG environment for designing web pages and then automatically produce the correct HTML codes.

For other examples of HTML, see dynamic HTML ; form ; frame ; Java ; JavaScript ; redirect ; table .