FLASH

Flash memory is nonvolatile memory, which is relative to SDRAM etc memory had said. Namely memory after powrefailure, internal data can still preserved. Flash according to the technical way into the NOR, Nand  And AG-AND Flash,  then upgrade . But after ten years later, there are still quite a few hardware engineer, confuse NOR and  NAND flash. Most cases flash just used to store a small amount of code, then NOR flash better. While NAND is high data storage density ideal solution.