Microprocessors are used in servers, desktop computers, laptops and mobile devices. They are popular in embedded devices, which traditionally use microcontrollers. Microprocessors were named to set them apart from larger processors used in the middle of the 20th century.
Microprocessors, which were far smaller than previous processors, lowered the cost of computers considerably and opened up the market for personal computers. As they became more powerful and required less energy, manufacturers began powering them with batteries and created laptops. Servers followed suit; microprocessors eventually became powerful enough to power even high-demand servers.
In the past, most embedded devices used microcontrollers that included RAM and other components. However, Linux, FreeBSD and other powerful, free operating systems have made microprocessors the preferred option for many embedded devices. Microprocessors make these devices easier to program, and they make trying different components simple.
Microprocessors power much of the Internet. Websites are run on servers using microprocessors, and many of the nodes that control Internet traffic rely on microprocessors as well. While Intel and AMD microprocessors dominate the industry, processors based on ARM designs have become more popular over the years thanks to mobile devices. Their low power usage is spurring their adoption in other areas as well.