Once audio has been sampled and converted to digital data, it can be processed and stored in a number of different formats. During the early development of digital audio, sound engineers devised formats for sampling and storing audio data that met the particular requirements of whatever operating system they happened to be using, and as a result, multiple formats emerged for the storage of digital audio.
As time passed, certain formats gained enough of a following to become de facto standards for certain applications. During the 1980s, with the advent of the personal computer, microprocessors increased in speed and capacity, and then during the 1990s, network access became commonplace, and new formats were developed to make the most of these technological advances as well as to meet emerging needs for compressed streaming audio and streaming media. Instead of the technology settling down to one or two established formats--as has happened with audio and video media in the past--the number of formats has increased rather than decreased.
A regular user of the internet confronts dozens of media formats for audio and video, and at this point, it seems doubtful that any one format will prevail. Fortunately, today's software can play files in most of the standard formats and files can be easily converted from one format to another.
In this section, we will review the formats used to capture, encode, and store digital audio. Of the dozens of audio formats that have been developed through the years, many are now used only infrequently, so we will look only at those that are likely to have some application in a library setting.