Computers and smartphones have different kinds of memory, which vary in speed and power efficiency depending on where they are used in the system. Typically, larger computers, especially those in data centers, will use a lot of magnetic hard drives, which are less common in consumer systems now. The magnetic technology these are based on provides very high capacity, but lack the speed of solid state system memory. Devices based on upcoming spintronic technology may be able to bridge that gap and radically improve upon even theoretical performance of classical electronic devices.