What’s asf

ASF stands for Advanced Systems Format, it’s Microsoft's proprietary digital audio/digital video container format, especially meant for streaming media. The most common file types contained within an ASF file are Windows Media Audio (WMA) and Windows Media Video (WMV). Note that the file extension abbreviations are different from the codecs which have the same name. When an ASF file is played back, content is delivered to you as a continuous flow of data. You no longer have to wait for the whole video and audio file fully download before you start to view them. As a result, this file format is specially designed to run on networks.