These computers usually do not have keyboards but rely on touchscreen technology for user input. Palmtops are typically smaller than a paperback novel, very lightweight with a reasonable battery life. A slightly larger and heavier version of the palmtop is the handheld computer . Workstation - A desktop computer that has a more powerful processor, additional memory and enhanced capabilities for performing a special group of task, such as 3D Graphics or game development . Server - A computer that has been optimized to provide services to other computers over a network .
Servers usually have powerful processors, lots of memory and large hard drives.
As the size of computers has diminished while the power has increased, the term mainframe has fallen out of use in favor of enterprise server . You'll still hear the term used, particularly in large companies to describe the huge machines processing millions of transactions every day. Minicomputers are normally referred to as mid-range servers now. This type of computer usually costs hundreds of thousands or even millions of dollars. Although some supercomputers are single computer systems, most are comprised of multiple high performance computers working in parallel as a single system.