alert.gif

GIF image Reference

A .gif file contains an image in the Graphics Interchange Format. The format supports up to 256 colors from a palette and uses lossless LZW compression. One file can hold many frames, thus simple animations are possible. The format is old, but web pages still use it for small animations. Photographs get better quality in formats such as PNG and JPEG.

A file extension is only a part of the file name. It does not give a guarantee about the format or the content of a file. But on Windows, the extension selects the program that opens the file.