Playblasting creates a movie by screen-grabbing your animation one frame at a time during playback, giving you a quick preview of the animation.
The Playblast window performs a screen grab of the animation in the active view at each frame during playback, then “blasts” the resulting images to the specified image viewer. The images can be saved either as a movie file or as a sequence of images in various formats. For more information, see Window > Playblast and Playblast animation.