HTML is the HyperText Markup Language.
HTML files are text files featuring semantically tagged elements.
HTML filenames are suffixed with .htm or .html.
Here's a simple HTML file:
<html>
<head>
<title>My First HTML Document</title>
</head>
<body>
<h1>A level one heading</h1>
Hello there. This is <STRONG>very</STRONG> important.
</body>
</html>
Look at this file in your web browser.
Names enclosed in angle brackets like <html>
,
<head>
, and <title>
are called tags. Tags are case
insensitive. <html>
means the same thing as
<HTML>
as <Html>
<HtMl>
. However, these days lower case tags
are preferred, especially if you need to work with XML or XHTML.
Most start-tags are matched with end-tags, and affect the text
contained between them. The end-tag is the same as the opening
tag except for a / after the opening angle bracket. For example,
</html>
, </head>
, and </title>
are end-tags. The text in between <title>
and </title>
, My First
HTML Document in the above example, is the title of the
page.
As you can see from the above example elements may, in general, nest. However they may not overlap (though some browsers can handle this).