File Formats

List of common file formats

Text

Suffix Short description Features Explanatory notes
.txt Plain text Pure text – no formatting Plain text files can have many different suffixes or even no suffix. They can easily be read or opened by any program that reads text and, for that reason, are considered universal.
.rtf Rich Text Format basic formattings RTF is a document file format developed by Microsoft in 1987 for cross-platform document interchange. Most word processors are able to read and write RTF documents.
.odt Open Document Text Formatted text, images and more objects File format of Open Office Writer and open for other applications.
.abw Format of AbiWord Formatted text, images and more objects AbiWord is a rich featured text editor but lightweight compared with OpenOffice.
.doc Format of Microsoft Word Formatted text, images and more objects Often used proprietary format.
.pdf Portable Document Format Formatted text, images and more objects PDF is used for representing two-dimensional documents in a manner independent of the software, hardware, and operating system. They are difficult to edit but you can create files in a different format and export the final Version as PDF (for example with OpenOffice). Very useful if you want to print a document anywhere else.

Audio

Suffix Codec (standard) Bitrate (standard) Explanatory notes
.wav PCM (uncompressed) 1411 Kbit/s ≈10 MByte/min Microsoft and IBM audio file format. Wav files may differ in the samplerate (standard: 44,1 kHz), bitrate (Standart: 16 bit/sample) and the number of channels (standard: 2 = Stereo). Wav files may also contain data encoded with other codecs than PCM but that’s very unusual.
.aif .aiff PCM (uncompressed) 1411 Kbit/s ≈10 MByte/min Audio interchange file format used by Apple Macintosh. May also differ in samplerate (standard: 44,1 kHz), bitrate (standard: 16 bit/sample) and the number of channels (standard: 2 = Stereo). The suffix .aifc should be used for compressed variants, but .aiff or .aif are usually accepted as well by audio applications supporting the compressed format.
.flac FLAC (lossless compression) ~760 Kbit/s ≈5.7 MByte/min FLAC is a lossless compression codec – it does not remove information from the audio stream. Lossy compression formats such as MP3, AAC, and Vorbis do remove information from the audio stream. lossless formats comparison

.shn Shorten (lossless compression) ~950 Kbit/s ≈7 MByte/min Shorten is no longer developed but remains a common format due to the large number of legally-traded concert recordings in circulation that are encoded as Shorten files. Being lossless, these files can be transcoded with the newer and more effective codecs without any loss.
.ogg Vorbis (lossy compression) ~128 Kbit/s ≈1 MByte/min Ogg is a free, open source container format supporting a variety of codecs – for example the open source audio codec Vorbis. Ogg Vorbis is said to provide a better quaility at the same bitrate in comparison to mp3. Not all mp3-players play Ogg Vorbis. Beside the samplerate, the bitrate and the number of channels; Ogg Vorbis files may differ in the intensity of the compression. A higher compression intensity provides smaller files with a lower quality. Vorbis supports VBR and CBR. VBR means that sequences with a more complex audio signal get a higher bitrate than sequences with less complexity.
.mp3 MPEG-1 Audio Layer 3 (lossy commpression) 128 Kbit/s ≈1 MByte/min mp3 files may also differ in the intensity of the compression. Normally mp3 files are compressed with CBR, but by now mp3 also supports VBR. The mp3 format is the most used lossy compression format for downloading and storing music, but it’s a proprietary format.
.aac .mp4 .m4a aac (lossy commpression) ~128 Kbit/s ≈1 MByte/min The AAC codec can be contained in many different container formats (.m4a, .m4b, .m4p, .m4v, .m4r, .3gp, .mp4, .aac). AAC generally achieves better sound quality than MP3 at the same bitrate. The usage of .mp4 files may be limited by DRM.
.wma WMA (lossy compression)   To be precise: there are four different WMA codecs existing: WMA, WMA Professional, WMA Lossless & WMA Voice. WMA is the most common one of these codecs. WMA is a proprietary format & the usage of .wma files may be limited by DRM.

Playlists

Playlists only contain links to audio or video resources. They don’t contain any audio or video data themselves.
.m3u M3U was originally implemented in Winamp, although it is now supported by many applications.
.pls PLS is a more expressive format than basic M3U, as it can store (cache) information on the song title and length (extended M3U supports this, too). Microsoft Windows and its software does not automatically detect PLS format and cannot run it.
.ram RAM files are sometimes encountered as links from web pages to audio streams using the proprietary RealAudio format.