Reel-to-reel, also known as open reel, is a term used to describe analog magnetic tape recording technology. This was a popular method of recording and playback in the mid-20th century. In recent years, the term has become less commonly used and has been replaced by newer recording methods such as digital recording. Some synonyms for reel-to-reel include tape recorder, magnetic tape recorder, and audio tape machine. These terms are all related to the use of magnetic tape for recording and playback. While not as commonly used as they once were, these terms remain important to the history and development of audio technology.