 The first modern memory cells were introduced in 1965, when John Schmidt designed the first 64-bit MOS SRAM (static RAM).In 1967, Robert H. Dennard of IBM filed a patent for a single-transistor DRAM (dynamic RAM) memory cell, using a MOSFET.The earliest practical application of floating-gate MOSFET (FGMOS) was floating-gate memory cells, which Dawon Kahng and Simon Sze proposed could be used to produce reprogrammable ROM (read-only memory).