record : to cause (sound, visual images, data, etc.) to be registered on something (such as a disc or magnetic tape) in reproducible form — Webster
recorder : a device that records sounds or images or both so that they can be heard or seen again — Webster
tape recorder : a device for recording on and playing back magnetic tape — Webster
Magnetic recording is a method of preserving sounds, pictures, and data in the form of electrical signals through the selective magnetization of portions of a magnetic material. The principle of magnetic recording was first demonstrated by the Danish engineer Valdemar Poulsen in 1900, when he introduced a machine called the telegraphone that recorded speech magnetically on steel wire.– Encyclopædia Britannica
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