One Interface to all Internet information

Multiple document formats

Most web publishing consists of making files available to the public. Commonly seen document/file formats on the WWW include:

Document Type	File Name
simple text	.txt, etc.
HTML hypertext (HTML)	.html [or .htm]
images (especially GIF and JPEG)	.gif or .jpeg [.jpg]
sounds	.au , .mid, .wav, etc.
video and animation	.mpg, .mov, .dcr, .class, etc.
Adobe Acrobat (PDF)	.pdf

anatomy of a web page