Audio post format
Displays audio player to play your audio files. Could be used for podcasting. Just insert a SoundCloud link or uploaded audio file anywhere into post content.
Gallery post format
Just insert a WordPress image gallery anywhere into the post content. The first 3 images are going to be displayed as a preview in posts listings.
Video post format
Displays a video player to play your video files. Could be used for video blogging. Just insert your video link or uploaded video anywhere into post content.