Solid State Storage

Solid state storage uses flash memory chips to store data. It is non-volatile, so the data remains when the power is off, and it has no moving parts: unlike a magnetic disk, nothing has to spin or move into position before data can be read.

Inside a flash chip, each memory cell holds a tiny amount of electric charge. Applying a current forces electrons across a barrier, where they stay trapped, and a current in the other direction releases them. Whether a cell is holding charge or not is what the computer reads as a 0 or a 1, so changing the charge is how the cell is written to or erased.

Advantages and disadvantages

Solid state storage is durable because there are no moving parts to knock or wear out. It is also very fast: reading and writing data needs no spinning disk or moving read/write head, so files open quickly and start-up is faster. It is silent and uses less power. However, it costs more than magnetic storage for the same capacity, and its capacity is broadly similar to that of magnetic disks.

Uses and flash memory

Solid state drives are built into laptops, tablets and smartphones, where being light, silent and hard to damage matters. Flash memory is the low-cost form of solid state storage: it is portable, small and tough, so it is used in removable memory cards and in small devices such as fitness trackers and handheld games consoles. A dash cam fixed to a van's windscreen is another good fit, because a bump or a drop is unlikely to lose the data.