by Jack Bennest » Wed Jan 14, 2009 2:56 am
clear as mud
The ICO file format is an image file format used for icons in Microsoft Windows. The CUR file format for cursors is almost identical, as the only differences are the identification byte and a specification of a hotspot in the header.
ICO files contain one or more small images at multiple sizes and colour depths.
The official IANA registered MIME type for ico files is image/vnd.microsoft.icon. Before this was registered, image/x-icon was the accepted option that complied with the rules of using x- for unregistered tokens. However, many others are seen, including image/ico, image/icon, text/ico, and application/ico. Many web servers do not come configured with a MIME type setting for .ico files, and may send their default MIME type, which might be text/html or text/plain.
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