Common Internet File Formats
Frequently Asked Qustions (FAQs) are just what the name says; a list or file of answers to common questions about a particular subject, usually asked by beginners. FAQs are an extremely valuable resource. They help you get up to speed quickly on a topic, without taking up other Internet users' time and resources. Almost all newsgroups, mailing lists, and other special interet groups maintain a FAQ file for new users.
.au, .aiff, .wav, Indicate sound files.
.gif, .jpg, .tiff, .bmp, Indicate image files.
.mpg, .mpeg, .mov, Indicate video files.
For a more extensive list of file formats, click here