Flash Memory

Flash memory is an electronic non-volatile computer memory that can be electrically erased and reprogrammed in place, built from floating-gate transistors and produced in two main forms, NOR and NAND flash. The Japanese engineer Fujio Masuoka invented flash memory at Toshiba in 1980; according to the company, a colleague named Shoji Ariizumi suggested the name because the process of erasing the memory reminded him of a camera flash, and Toshiba began marketing the technology commercially in 1987. NOR flash allows random access to individual bytes and can run code directly from the chip, while NAND flash reads and writes in larger blocks but achieves much higher storage density and lower cost per bit, which let it overtake NOR in sales by 2005 and made it the basis of memory cards, USB drives and solid-state drives.