A tape recorder is a device that uses electromagnets to record and play back sound. Once the sound is recorded, it can then be reproduced using the player component that almost any tape recorder will have. It was the dominant audio technology during the last several decades of the 20th century.
These devices work by running a tape coated with a type of iron oxide over the electromagnetic head of the machine. Depending on what its function is at that particular time, new information can be put on the magnetic tape or it can be read back. Due to the use of magnets, the audio cassette is highly susceptible to magnetic fields and therefore needs to be kept away from all magnets. This is one of the easiest ways to damage a recording. The tape recorder was the precedent of the video recorder, which is still in widespread use today. The basic technology between the two is very similar.
The cassette used in a recorder can be the standard size, or one much smaller, which is known as the microcassette. Either way, the function of the tape recorder remains the same. A microcassette is often used as a voice recorder, though it is capable of recording music as well.
As a recording device, this device had a number of advantages over other machines at the time it became popular. First, its size made it easy to handle and very portable. Second, its ability to immediately play back a recording was also seen as an advantage. There was no other processing needed before hearing what was said or recorded.
However, there were a number of disadvantages with these machines as well. For example, eventually the tape will wear out, leading to a diminished quality of sound or perhaps making the tape impossible to play or hear at all. Also, tape recorders, if they got too old or were not maintained properly, could tangle up the tape inside the machine, an event many have referred to as "eating" the tape.
Due to those limitations, newer technologies have all but replaced the tape recorder. Compact disc players are used for higher-quality music playback. While the microcassette remained popular for a while, even that has been replaced by digital voice recorders.
The tape recorder can sometimes function as a multi-use device. Many include radios, for example. When compact discs became popular, many still used cassette tapes regularly. Therefore, the popular item was a tape player that also doubled as a CD player and radio. With the declining popularity of cassette tapes, these multi-use devices are getting harder to find.