MIME types

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Revision as of 17:09, 19 February 2007 by Np (talk | contribs) (→‎Configuring MIME types: previous url is 404, this may not be best but it's something)
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MIME types (content types) tell the browser what to do with content sent to it.

Common MIME types

MIME Type Result
application/octet-stream Download
text/plain Display as plain text
text/html Render as HTML

Results of sending as the wrong type

Sending the wrong MIME type can result in a file being downloaded instead of displayed, displayed instead of downloaded, or displayed improperly. You can see what MIME type your server is sending by using "Tools -> Page Info" in Firefox ("View -> Page Info" in Mozilla Suite) or you can use the Live HTTP Headers extension. Internet Explorer uses non-standard and insecure "sniffing" to sometimes override what the server tells it, so the oversight is not always apparent at first.

Configuring MIME types

Server-side scripts

If you are using a server-side scripting language to generate content, the appropriate content-type response header must be sent as well as the content itself. How this is accomplished depends on what language is being used. The following is an example using Perl:

print "Content-Type: text/html; charset=utf-8\n\n";
print "<html>\n";
print "<head>\n";
print "<title>Hello World!</title>\n";
print "</head>\n";
print "<body>\n";
print "<p>Hello World!</p>\n";
print "</body>\n";
print "</html>\n";

The first line of the above Perl script will identify the content as text/html and the browser will render it as such. Refer to the documentation of your scripting language for information about sending the appropriate content-type.

Related links