MIME Content Types

MIME Content Types consist of a type (such as `` text'') and a subtype (such as `` html'').

The most common MIME types relevant to the WWW are:

• A `` text'' Content-Type, which is used to represent textual information in a number of character sets and formatted text description languages in a standardised manner. The two most likely subtypes are:
  • text/plain - text with no special formatting requirements.
  • text/html - text with embedded HTML commands

• An `` application'' Content-Type, which is used to transmit application data or binary data. Two frequently used subtypes are:
  • application/binary - the data is in some unknown binary format, such as the results of a file transfer.
  • application/postscript - the data is in the postscript language, and should be fed to a postscript interpreter.

• An `` image'' Content-Type, for transmitting still image (picture) data. There are many possible subtypes, but the ones used most often on the web are:
  • image/gif - an image in the GIF format.
  • image/xbm - an image in the X Bitmap format.
  • image/jpeg - an image in the JPEG format.

• An `` audio'' Content-Type, for transmitting audio or voice data.
  • audio/basic - the data consists of 8KHz 8 bit mu-law audio samples. This is the standard way that audio is encoded digitally for the telephone system in the US and Japan, and because of this, many inexpensive hardware devices exist now on computers for input and output in this form. Basically, the analog audio is sampled in 8 bit chunks 8000 times a second, and each chunk assigned a "pulse" value. mu-law refer to the way the "sound" of the pulse is converted to an 8 bit values.

• A `` video'' Content-Type, for transmitting video or moving image data, possibly with audio as part of the composite video data format.
  • video/mpeg - the data is MPEG format video
  • video/quicktime - the data is QuickTime format video