Today's rapidly changing technology has been catalyzing a jungle of media formats out there, which makes it not always easy to keep track of what's what and what will work with which players. This media glossary may give you some clue to round out the jungle:

WMA	MP4	MOV	VOB	MP3	FLAC
WMV	M4A	OGG	AVI	3GP	Xvid
WAV	M4B	AC3	FLV	APE	DivX
AAC	M4V	M4P	ASF	MKV	ALAC
Bit Rate	Sample Rate	H.264	Frame Rate	Resolution	AIFF

 

WMA - is Microsoft's main audio format and is available in both lossy and lossless variations. The lossy version is most used and with DRM stuck to it.

Players Supported: Zune, Creative Zen, Blackberry, Cowon, iRiver, Archos, PSP

Converter Available: All Media Converter; All Music Converter; WMA Converter

WMV - Windows Media Video, normally use the ASF container and the files end in either .wmv or .asf. The file ending is irrelevant and you could rename asf to wmv and it would still work. WMV is a group of codecs just like MPEG-4.
Players Supported: Zune, Creative Zen, PSP, Blackberry, Archos, Cowon, iRiver
Converter Available: All Media Converter; All Video Converter; WMV Converter

MP4 - MPEG-4 Part 14, is a multimedia container format standard specified as a part of MPEG-4, most commonly used to store digital audio and digital video streams, official filename extension is .mp4.

Audio-only MPEG-4 files generally have .m4a extension.

Audio book and podcast files more commonly use the .m4b extension.

The Apple iPhone uses MPEG-4 audio for its ringtones but uses the .m4r extension.

MPEG-4 files with audio streams encrypted by FairPlay Digital Rights Management as sold through the iTunes

Store use the .m4p extension.

The common but non-standard use of the extensions .m4a is due to the popularity of Apple’s iPod, iPhone, and

iTunes Store, and Microsoft's Xbox 360 and Zune. Without mods, Sony's PSP can also play m4a. m4a generally delivers better audio quality than the older MP3 format at the same bit rate.

Players Supported: iPod, Zune（except Zune30）, Creative Zen, Blackberry, Archos, PSP, Cowon, iRiver

Converter Available: All Media Converter; All Video Converter; M4P Converter

AAC - Advanced Audio Coding, packed in a variety of container formats as .mp4 .m4a or .m4b, is a standardized, lossy compression and encoding scheme for digital audio. Designed to be the successor of the MP3 format by achieving better sound quality at many bit rates. AAC's best known use is as the default audio format of Apple's iPhone, iPod, iTunes most for DRM protection, as well as Sony’s PlayStation 3, PSP, Sony Walkman.

Players Supported: iPod, iPhone, Zune, Creative Zen, Archos, PSP, Blackberry

Converter Available: All Media Converter; All Music Converter; M4P Converter

H.264 - H.264/AVC (Advanced Video Coding) is an industry standard for video compression based on MPEG-4 Part 10, delivers MPEG-4 quality with a frame size up to four times greater. It can also provide MPEG-2 quality at a reduced data rate, requiring as little as one third the original bandwidth.
Players Supported: iPod, iPhone, Zune（except Zune30）, PSP, Blackberry, Archos, Cowon
Converter Available: All Media Converter; All Video Converter; iPod Media Converter; iPhone Media Converter

M4V - raw MPEG-4 Visual bit streams, named .m4v, is a standard file format for the popular Apple iPod devices. Another definition is that download videos from the iTunes store are in m4v format, along with videos that are converted in iTunes.
Players Supported: iPod, iPhone, Zune, Creative Zen
Converter Available: All Media Converter; M4V Converter;

MOV - the QuickTime (.mov) file format functions as a multimedia container file that contains one or more tracks, each of which stores a particular type of data: audio, video, effects, or text (e.g. for subtitles).
Players Supported: iPod, iPhone, Zune, Blackberry
Converter Available: All Media Converter; iPod Media Converter; iPhone Media Converter

WAV - short for Waveform audio format, is a Microsoft audio file format standard for storing an audio bitstream on PCs.the main use is for totally uncompressed audio both quality wise and size wise.
Players Supported: iPod, iPhone, Creative Zen, PSP, Blackberry, Cowon, iriver
Converter Available: All Media Converter; All Music Converter; ZEN Media Converter

AC3- is the common version containing up to six discrete channels of sound, the most elaborate mode in common usage involves five channels for normal-range speakers, supports audio sample-rates up to 48 kHz.
Players Supported: Zune, Archos, Cowon
Converter Available: All Music Converter; Zune Media Converter

3GP - Mobile phones use 3GP, a simplified version of MPEG-4 Part 12 with the .3gp and .3g2 extensions. (for GSM-based Phones, may have filename extension .3gp，for CDMA-based Phones, may have filename extension .3g2)
Players Supported: Zune, Blackberry
Converter Available: All Media Converter; Blackberry Media Converter; Nokia Media Converter

AVI - Audio Video Interleave, known by its acronym AVI, is a multimedia container format introduced by Microsoft in November 1992 as part of its Video for Windows technology. AVI files can contain both audio and video data in a file container that allows synchronous audio-with-video playback.
Players Supported: Zune, PSP, Blackberry, Cowon
Converter Available: All Media Converter; All Video Converter; PSP Media Converter

ASF - Advanced Systems Format, is Microsoft's proprietary digital audio/video container format, especially meant for streaming media. asf is part of the Windows Media framework.
Players Supported: Zune, PSP, Blackberry, Cowon, iRiver
Converter Available: All Media Converter; Zune Media Converter; PSP Media Converter

OGG - is a free, open standard container format, commonly used to refer to audio file format Ogg Vorbis, that is, Vorbis-encoded audio in the Ogg container.
Players Supported: Zune, Cowon, iRiver
Converter Available: All Media Converter; All Music Converter

APE - Monkey's Audio, aka APE, is a lossless format that is supported by a very small number of players.
Players Supported: Zune, Cowon, iRiver
Converter Available: All Media Converter; Zune Media Converter

VOB - (Video Object) is a container format contained in DVD-Video media. VOB is based on MPEG-2 program stream format, contains the actual Video, Audio, Subtitle, and Menu contents in stream form
Players Supported: iPod, Zune, Creative Zen, Archos, PSP, Cowon
Converter Available: All Media Converter; All Video Converter

MKV - Matroska, the extensible open standard Audio/Video container that can hold an unlimited number of video, audio, picture or subtitle tracks inside a single fileMatroska, usually found as .mkv files (matroska video) and .mka files (matroska audio).
Players Supported: Cowon
Converter Available: All Media Converter; All Music Converter

FLV - Flash Video with the extension .flv, is a file format used to deliver video over the Internet via Adobe Flash Player, Flash Video content may also be embedded within .swf files. Notable users of the Flash Video format include YouTube, Google Video, Yahoo! Video, Reuters.com
Converter Available: All Media Converter; All Video Converter

MP3 - is an acronym for MPEG-1 (or MPEG-2) Layer 3 audio encoding (it is not an acronym for MPEG-3). MP3 is a popular compression format used for audio files on computers and portable devices.
Players Supported: iPod, iPhone, Zune, PSP, Creative Zen, Blackberry, Archos, Cowon, iriver
Converter Available: All Media Converter; All Music Converter

DivX - is a brand name of products created by DivX, Inc. including the DivX Codec which has become popular due to its ability to compress lengthy video segments into small sizes while maintaining relatively high visual quality. The DivX codec uses lossy MPEG-4 compression, where quality is balanced against file size for utility.
Players Supported: Zune, Creative Zen, Blackberry, Cowon
Converter Available: All Media Converter; All Video Converter

XviD - is an open video codec library distributed under the terms of the GNU by following the MPEG-4 standard, primary competitor of the DivX, can be used on all platforms and operating systems
Players Supported: Zune, Creative Zen, Blackberry, Cowon
Converter Available: All Media Converter; All Video Converter; ZEN Media Converter

FLAC - Free Lossless Audio Codec (FLAC) is a file format for lossless audio data compression, reduces bandwidth and storage requirements of the audio source with file size reduced 40% to 50%.
Players Supported: Zune, Cowon, iRiver
Converter Available: All Media Converter; All Video Converter; Zune Media Converter

AIFF - Audio Interchange File Format, co-developed by Apple and IFF, is an audio file format standard used for storing sound data for personal computers and other electronic audio devices, most commonly used on Apple Macintosh computer systems with file extension .aiff or .aif
Players Supported: iPod, iPhone
Converter Available: All Music Converter; iPod Media Converter; iPhone Media Converter

ALAC - Apple Lossless, known as Apple Lossless Encoder (ALE), or Apple Lossless Audio Codec (ALAC), is an audio codec developed by Apple Inc. for lossless data compression of digital music. ALAC data is stored within an MP4 container with the filename extension .m4a
Players Supported: iPod, iPhone
Converter Available: All Music Converter; iPod Media Converter; iPhone Media Converter

Bit Rate - Bit rate is basically just how much space the audio or video file uses per second, measure in unit of Kbps usually. The higher the bit rate, the bigger the file, and the better the quality will be because you'll have more space per second to avoid compressing the quality too much.

Sample Rate - A term to define characteristic of any digital audio signal. This refers to how frequently the analog signal is measured during the sampling process. However, the higher the sample rate the more memory is required to store the samples.

Resolution - simply refers to the dimension of the screen image, in terms of the number of pixels wide by the number of pixels high (ie, 640x480).

Frame Rate - or frame frequency, is the measurement of the frequency (rate) at which an imaging device produces unique consecutive images, often expressed in frames per second (FPS) and in progressive-scan monitors as hertz (Hz), the higher the better, but both 25 and 30 should be sufficient, and increasing frame rate to a higher one than the source file has no purpose whatsoever.