NAND flash memory stores data in pages but erases in blocks – a fundamental asymmetry that shapes everything from SSD performance to all-flash array design. This article explains the program/erase cycle and why it matters for database storage.

NAND flash memory was invented in 1981 by Dr Fujio Masuoka at Toshiba. This article explains how flash works, why it differs from EPROM and EEPROM, and why program and erase operations behave differently.