asf The .asf filename extension refers to the Microsoft owned audio and digital video container, advanced systems format. It is a container for windows media audio and windows media video but shares the same internal structure as both WMA and WMV file formats. The format was designed with the goal of increasing efficiency in distribution of audio video files across computer networks. However, it works just as well for local system playback. The asf format forms part of Microsoft's Foundation framework. The major feature of the format is its ability to add digital rights management by providing the framework for encrypting audio and video files.
aiff The audio interchange file format, and its associated .aif filename extension, is one of the earliest uncompressed audio file formats released for personal computers. The format had its initial release in 1988 and was developed by Apple Inc. using the IFF ' interchange file format, developed by Electronic Arts, as a template. Because the format is inherently lossless, files tend to be large when pitted against lossy audio file formats. Because of this, .aif files are best suited for local storage and playback.