Saviour of the universe

摘要

Imagine a mobile phone that lost all its numbers when you took out the battery. Or a digital camera that you had to keep charged, otherwise your holiday snaps vanished. Both would be pretty useless to most of us. And while we might expect a really old radio to lose the stations we've stored if it's unplugged, we don't expect it of a new one. Whether we remember to charge it up or not, we assume our MP3 player will have all our tunes, just as soon as it's powered up. For all these things, we rely on non-volatile memory, which carries on holding data when the power is removed. In most modern devices, that means Flash memory - compact, cheap, and found inside just about everything electronic.