FLV (Flash Video) is a video container format developed by Adobe Systems and comes with a .flv filename format. FLV is primarily used to stream audio, video, and text data such as subtitles. It supports MPEG-4 Part 10 (H.264) video codec and AAC sound.
RealPlayer, Apple QuicTime Player
VLC Media Player
APE (Monkey’s Audio) is a lossless audio file format released in 2000 by Matthew T. Ashland. Because it’s a lossless sound format, it doesn’t lose data during compression, unlike other standard formats like AAC, MP3, and Vorbis. However, Monkey’s Audio is available on PC only. To play APE on Mac OS X and Linux, you’ll need a third-party plugin like JRiver Media Center.