Wikimedia
Wikipedia: Gif (Graphics Interchange Format)
Encyclopedia entry that defines a GIF (Graphics Interchange Format) graphics file and explains how and why it was created. Sections of the article include history, Unisys and LZW patent enforcement, usage, color, alternatives,...
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Elated Communications: Understanding Image Formats
This tutorial looks at the three common image formats used on the web: GIF, JPEG and PNG. You'll learn how these image formats work, and where to use each type of image in your web pages.