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.................... Introduction to HTML

3.4 META

META is a general element for document meta-information -- that is, for information about the document that cannot be expressed by LINK, BASE or the other HEAD elements. There are two ways this can be expressed.


3.4.1 HTTP-Equivalent META Information

Sometimes you want a header to contain information that would ordinarily be returned by the server as a field in the HTTP headers. For example, you could use META to include an expiry date for files that are periodically updated. The META element would be:
   <META HTTP-EQUIV="Expires"   CONTENT="25-Dec-1995  12:00:00 GMT">
You should not use this to override a header that is actually sent by a server, so don't use this to return things like content-type.

Netscape Extension to META

Netscape browsers support the special META element
   <META HTTP-EQUIV="Refresh" CONTENT="12; URL=http://foo.bar/blatz.html">
The browser recognizes this as a special "refresh" header and, after a delay of 12 seconds, accesses the indicated URL. Alternatively, you could have written a META element such as:
   <META HTTP-EQUIV="Refresh" CONTENT="10">
in which case the browser would wait 10 seconds and then re-access the currently displayed document.
NOTE:
Most browsers ignore META elements and their content -- Netscape is the only browser I know of that pays attention to this element, and then only for the special case HTTP-EQUIV="Refresh".

3.4.2 Arbitrary User-Specified META Information

A user might want to include information about the document, such as keywords for indexing, the name of the author, and so on. This can be done with META elements such as the following:
   <META NAME="author"   CONTENT="Ian Graham">
   <META NAME="keywords" CONTENT="html documentation web url">
   <META NAME="editor"   CONTENT="HTML SuperPro">
The attribute NAME refers to arbitrary user-selected names, while HTTP-EQUIV means that the value has a real equivalent header in the HTTP protocol. Again this is only really useful given tools for processing these data. At present, there are very few tools that take advantage of META element content.
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© Ian Graham 1994-1995 Page Last Updated: 4 December 1995