Flash memory
Flash memory is a block-erasable, non-volatile semiconductor memory invented by Fujio Masuoka at Toshiba in 1980. It builds on EEPROM but replaces byte-wise erasure with faster block-wise erasure — enabled by floating-gate transistor design. The name 'flash' was coined by colleague Shōji Ariizumi to reflect that speed. Masuoka and colleagues presented NOR flash in 1984 and NAND flash at the 1987 IEDM. Toshiba began marketing flash memory and commercially launched NAND flash — both in 1987. The first published implementation held only 8192 bytes but became the basis for larger-capacity versions. Flash does not support byte-level writes or in-place updates; erasure is all-or-nothing per block. It cannot replace RAM or true EEPROM where fine-grained modification is required. Flash changed how portable devices store firmware and user data, enabling compact, shock-resistant, low-power storage that scales without moving parts — a prerequisite for digital cameras, USB drives, SSDs and smartphones.