PHP Headers and Popular Mime Types

Atom

header('Content-type: application/atom+xml');

Javascript

header('Content-type: text/javascript');

JPEG Image

header('Content-type: image/jpeg');

PDF

header('Content-type: application/pdf');

XML

header('Content-type: text/xml');

RSS

header('Content-Type: application/rss+xml; charset=ISO-8859-1');

CSS

header('Content-type: text/css');