Card Capacitor—A Semipermanent, Read Only Memory [Letter to the Editor]

The random access, high-speed memories most frequently used today are of the magnetic core type, which have the ability to be read from and written into at speeds of the order of a few microseconds. In some applications another form of memory can be used that may be read at these high speeds, with capability of being changed in a few minutes. Memories of this type, in which the fast-read cycle is of prime importance, may be called READ ONLY memories.