Recognizing file formats

Multimedia content may be viewed live on stage, or may be projected or transmitted. The content may also be played locally using a media player. If the content is broadcast, the broadcast may be live or recorded earlier. Digital online multimedia may be accessed by downloading the content or by streaming, which may be either live or on demand. Interactivity in multimedia is enhanced by combining several forms of media content. Many forms of online multimedia are increasingly becoming object oriented as well as data driven, which makes it possible to have applications with end-user collaboration and innovation as well as personalization of various types of content over time. This would include photo galleries with images accompanied by text that is user updated, as well as simulations whose parameters, illustrations, animations, and videos can be modified, allowing the multimedia experience to be altered without the need for reprogramming.

To identify the type of file, an extension is added to the filename when it is saved on disk.

	Common text extensions: .pdf (portable document format) .doc (MS Word document) .rtf (rich text format) .htm or .html (hypertext markup language for Web files)
	Graphics include charts, photos, drawings, buttons, etc. .gif (graphics interchange format) .jpg (jpeg- joint photographic experts group) .tif (tagged image file)
	Video refers to recording, editing and displaying moving images. Common formats: .avi (audio video interleave) .mov (QuickTime movie) .mpg (mpeg- moving picture experts group)
	You can hear sound such as songs, movie soundtracks and speeches. Common audio formats: .wav (Windows wave audio format) .ra (RealAudio file) .mp3 (compressed music files)
	Animations are made up of a series of independent pictures put together in sequence to look like moving pictures. Common formats: .gif for animated gifs .swf for Flash files
	Files compressed with Winzip have a .zip extension. A popular format used to compress and distribute movies on DVDs or over the Net is DivX,a digital video codec (COmpress, DECompress).