Reel-to-Reel
Open-reel or reel-to-reel tape (same thing) is the format of magnetic audio tape in which the tape is held on a reel or spindle rather than being enclosed in a cartridge or cassette.
Two reels are needed to record or play the format: the feed reel and the take-up reel. The feed or supply contains the tape, the end of which is manually pulled out of the reel, fed into the tape head assembly and attached by friction to the hub of the take-up reel. As the tape records or plays, the feed reel empties and the take-up reel fills.
The tape machine (player and/or recorder) uses motors to wind the tape from one reel to another, passing it over tape heads to read, write or erase the tape’s information as it moves.
Dave Denyer: The Reel-to-Reel Rambler (link)
