AAC:
Advanced Audio Coding is a latest audio codec developed by Fraunhofer. It is becoming more popular because of its audio quality and the file size. It offers high audio quality at lower bit rates. And many of the mp4 players now support AAC file formats.

AIFF:
This is the default sound file format in Macintosh computers. And it is supported by Apple iPods.

Apple:
Apple is the leading manufactures of iPods. iPods supports mp4 file formats. There are many variations available in Apple iPods. And the mp4 format is supported by each of these variations.

Automatic Music Search:
Automatic Music Search usually abbreviated as AMS is a piece of software found in mp4 players. It is used for searching the music files that are available in the player and enables jumping between the music tracks.

Bit Rate:
Bit rate refers to the speed at which the audio data travels per second. And the bit rate varies for different file formats and it depends on the ripping method used.

CDA File Format:
CD – Audio file format is the original audio available in the audio cds. Later these files can ripped to any of the format like mp3, mp4, etc that can be played in mp4 players.

Codec:
Codec is the abbreviated form of compression/decompression. It is a piece of software that is used to compress and decompress the audio files.

Constant Bit Rate:
Constant Bit Rate commonly known as CBR. When the audio is ripped in CBR the bit rate of the audio file remains same throughout the file.

Convertor:
Convertor is software that is used to transform one file format to the other. Many freeware convertor softwares are available and it can be utilised to convert the audio and videos to your desired file format.

Decoding:
MP4 players decode the mp4 audio and video files so as to play the data format as audio and video. And the term is normally refers to the conversion of mp4 file format to wave format.

Digital Tuner:
Digital tuner is almost available in all the mp4 players which are used for tuning of the radio stations. And it supports both the manual and automatic tuning of the radio stations.

Earbuds:
This is the small, circular device that you can put in to the ears so as to listen to the audio from the mp4 players. It provides the same functionality as that of the headphones.

Flash Cards:
Flash cards are the type of storage available in mp4 players for the storage of songs and videos. Latest mp4 players are designed with the capability to expand the memory via external memory sticks.

Giga Byte:
GB is a unit used to measure the memory capacity.  MP4 players now come with 2GB, 4GB, etc of data storage capacity.

GIF:
Graphics Interchange File Format is a lossless image compression technique. And it supports 256 colours.

Firewire:
Firewire is the Apple’s name for the IEEE 1394 and it is used as a high speed external bus standard with data transfer rates up to 400Mbps.

Headphones:
Headphones allow the users to listen music personally without disturbing the others and enable you to enjoy the quality of music to the core. Headphones come with many of the latest techniques like stereo effect, etc.

iPod:
iPods are the most popular gadget from Apple. It offers high quality music output and has been provided with huge storage capacity.

iTunes:
iTunes is the software provided by Apple for managing songs and videos in the iPod. iTunes is freeware software available for the iPod users and it has been designed with a user friendly interface.

Joint Photographic Experts Group:
Joint Photographic Experts Group commonly known as JPEG is an image compression technique used for compressing image files. It supports 16 millions colours. And most of the latest mp4 players support JPEG file format.

Liquid Crystal Display:
Liquid Crystal Display is the type of display available in all types of mp4 players. And it offers high quality of video display with larger aspect ratio, contrast, brightness, etc. And the display of mp4 players come with various resolutions, that offers high quality video display.

Memory Card:
Memory card is the removable storage media used in many of the latest electronic gadgets like mobile phones, mp4 players, iPods, digital video cameras, camcorders, etc.

MP3:
MP3 is a multimedia format specified as a part of MPEG. It is a lossy data compression technique. And the maximum bit rate available in mp3 audio format is about 320 kilo bits per seconds and the most commonly used bit rate is 128 kbps.

MP4:
MP4 is a multimedia format specified as a part of MPEG-4. It is used for storing digital audio and digital video files. Apart from these, it is also used for storing other file such as subtitles, image files, etc.

Playlist:
This is the way of organising the music and video files according to the kind of song, based on their genre, and based on your wish.

Real Player:
This is the media player software similar like windows media player. It has been provided with codec that supports real media files.

Thumbnail:
It is the small version of a photo or video that can be viewed once the folder in the mp4 player is opened. It helps in easy identification of various video and image files.

TIFF (Tagged Image File Format):
TIFF is the tagged file format that is used to store the image files with .tif extension. Most of the latest mp4 players support TIFF file format.

Variable Bit Rate:
Variable Bit Rate commonly known as VBR. When the audio is ripped in VBR the bit rate of the audio file varies randomly.

Version:
Version number indicates the current version of the mp4 player’s software.