How does a USB memory stick work?

The world's highest capacity flash drive can hold up to a terabyte of data - but how can you fit all of that information into a box the size of your thumb?

By Gareth Mitchell

Asked by: Mark Reiderman, Belgium

The chip inside contains a grid of transistors acting like tiny switches. All data is reduced to binary 1s and 0s and one of these values is stored at each point in the memory. To store a ‘1’, the transistor in the relevant location is switched on, allowing charge to flow through it. The transistors stay in their on or off states even with no power, so the data stays intact even when you disconnect your memory stick.

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