Microcomputers include desktops, laptops, and tablets. They are designed for single user use and contain a processor, memory, and input/output devices. Mobile devices like smartphones and handheld computers store programs and data on internal memory or removable cards. Minicomputers are larger and more powerful than desktops, able to serve hundreds of users simultaneously through personal computers. Mainframe computers contain multiple processors and are designed for large scale, multi-user tasks. Supercomputers are the most powerful and expensive computers, using thousands of microprocessors to perform complex calculations.