Videodisc Recorder – A machine that records a TV program onto a videodisc.

Level 1 Videodisc Player - Usually a consumer model player with features such as two-channel, chapter stop, picture stop, scan, and audio freeze frame, but with no computer memory.
Level 2 Videodisc Player - An educational/industrial videodisc player, usually with all the level 1 capabilities plus a small computer.
Level 3 Videodisc Player - A videodisc player that’s hooked up to an external computer. The computer program, which may be received from a floppy diskette, controls the sequences the videodisc player will play.
Level 4 Videodisc Player - A videodisc player usually with a built-in computer. It’s able to read large computer programs.
Level 1/2/3 videodisc Player - A combination level 1, level 2, level 3 videodisc player.