ABSTRACT
For mass computer memory, it is essential that either much information has to be stored in one material unit, or a large number of elements and selection circuits have to be combined to act as one element that can store much information. As examples of the former type, ultrasonic delay line, magnetic tape, and disk can be mentioned. As for the latter, we can refer to the magnetic core memory that is created by attaching I-bit ferrite cores at the cross points of a woven insulated wire, and integrated circuit (IC) memory that is built up from two parts: microcapacitors, each storing 1 bit of information corresponding to existing or nonexisting electrostatic charge, with selection circuits incorporated.
