A vieo server is a computer based device (also called a 'host') dedicated to delivering video online. Unlike PCs or Macs, both being multi-application devices, a video server is designed for one purpose; provisioning video. A professional grade video server records, stores, and plays back multiple streams of video without any degradation in the video signal. Broadcast quality video servers often store hundreds of hours of MPEG-2 compressed video, play out three or more simultaneous streams of video, and offer quality interfaces such as SDI for digital video and XLR for balanced audio.