HTML and CSS Reference
In-Depth Information
ignore the text between the comment character sequences. Here are
some sample comments:
<! This is a comment >
<! This is a
multiple-line comment
that ends on this line >
There must be a space after the initial
<!
and preceding the final
>
, but
otherwise you can put nearly anything inside the comment. The biggest
exception to this rule is that the HTML standard doesn't let you nest
comments.
[*]
[*]
Early versions of Netscape did let you nest comments, but no longer. The practice is tricky, so just
say no.
Internet Explorer also lets you place comments within a special, non-
standard
<comment>
tag. Everything between the
<comment>
and
</comment>
tags is ignored by Internet Explorer. All other browsers dis-
play the comment to the user. Obviously, because of this undesirable
behavior, we do not recommend using the
<comment>
tag. Instead, al-
ways use the
<!--
and
-->
sequences to delimit comments.
Besides the obvious use of comments for source documentation, many
web servers use comments to take advantage of features specific to the
document server software. These servers scan the document for specif-
ic character sequences within conventional HTML/XHTML comments and
then perform some action based upon the commands embedded in the
comments. The action might be as simple as including text from another
file (known as a
server-side include
) or as complex as executing other
commands on the server to generate the document contents dynamic-
ally.
