WAV (WAVE) files are audio files playable via multimedia playback software such as Windows Media Player and other software available for your operating system. These files contain any sounds such as sound effects, music or spoken words. WAV files are large in size and with the advent of MP3 and MP4 WAV files are becoming less popular and less common. They were created and developed by IBM and Microsoft but unlike MP3 and MP4 the WAV file format does not use a form of lossy compression so file sizes are therefore much bigger and now less popular.
Wav files are the standard digital audio format in Windows. Using the .WAV file extension, 8- or 16-bit samples can be taken at rates of 11,025 Hz, 22,050 Hz and 44,100 Hz. The highest quality being th 16-bit at 44,100 HZ, this highest level is the sampling rate of an audio CD and uses 88KB of storage per second. All general sounds in Windows, such as when you log in, are in the .WAV format. The default content of a WAV file is uncompressed (although they can be used to store compressed formats such as MP3), pulse code modulated (PCM) digital samples derived from the analog source.
Associated programs
CyberLink PowerDirector Microsoft Windows Media Player Roxio Creator 2009
AAC is similar to MP3. It essentially cuts out, or compresses, information that the human ear cannot pick up thereby making digital files smaller and more easily managed and therefore quicker to download. AAC is about half the size of MP3 but with better quality. It is at least one tenth the size of CD digital data. Apple are the biggest users of this format and if you have an iPod or iPhone then you will have come across this format as it is iTunes default audio format.
AAC is similar in concept to MP3 but goes further. It too compresses digital audio files but to a bigger degree. It is also part of the MPEG-4 standard, it is most widely used to create small digital audio files. The current variant is specified in ISO/IEC standard 14496-3. Like MP3, AAC is a lossy algorithm. The human hearing system cannot hear quiet sounds in the presence of loud sounds of a similar frequency; for example, a voice conversation cannot be heard while an aeroplane flies low overhead. This is known as auditory masking, this allows the discarding of data with minimal loss of quality.
Associated programs
KMPlayer RealPlayer VideoLAN VLC Media Player Windows Media Player iTunes
Developed by
A combination of Fraunhofer IIS, AT&T Bell Laboratories, Dolby and Sony Corporation
