A data identification scheme used to convey the type of file being encoded or transferred. MIME stands for Multipurpose Internet Mail Extensions.

Common mime types include:

  • text/plain - Plain text
  • text/html - HTML documents (web pages)
  • audio/wav - standard WAV audio
  • image/gif - GIF images
  • image/jpeg - JPG images
  • image/bmp - BMP images
  • video/avi - AVI video
  • video/mpeg - MPG video
  • application/postscript - Adobe postscript
  • application/pdf - Adobe PDF
  • application/octet-stream - generic unknown format

As far as details on implementation for a web server, here's a little bit of information about MIME types from Netscape's knowledge base:

The purpose of associating file extensions with MIME types on a web server is to enable the server to tell a browser specifically what kind of file is being downloaded, without relying on the browser to know every possible file extension. For example, you would tell your web server all of the extensions that specify JPEG images on your server (these could be ".jpg", ".jpeg", and ".jpe") and associate these with a MIME type of "image/jpeg". This allows the browser to identify the file type and determine how to display files with the JPEG extensions.