The following comes from an original TCM Boston label concerning semiconductors: Semiconductor Memories With the invention of the transistor and the integrated circuit, it was possible to fabricate a complete array of memory cells using the Metal Oxide Semiconductor technology in a large scale integrated circuit configuration. Although smaller memory arrays were fabricated prior to 1972, the array of 32 x 32 x 1 (1,024 bits) was the first memory chip to be useful as a primary memory element. Subsequent larger memory arrays became even more cost effective and eventually replaced core as the dominant primary memory. The chip memories included the 4,096 bit chip, 1974; the 16,384 bit 1976; and 65,536 bit chip, 1978. Using a rapid technology improvement model of doubling bits every two years, a 1 million bit chip would first appear in 1982.