Types of Computers

There are many different types of computers available including:

Mainframes
Are large centralized computers found in sizeable enterprises and purchased through specialized resellers.

Servers
Servers are high performance computers used in businesses and other organizations. Servers provide services to many end users or clients.
Laptops

Laptops, also called notebooks, are comparable to desktops in usage and processing capability. However, they are portable devices built to be lightweight and use less power, with a built-in mouse, monitor and keyboard. Laptops can also be plugged into a docking station which allows the user to utilize a larger monitor, mouse, full-sized keyboard and have more connection options.
Despite this, laptops have a limited number of configurations available, such as video options and connection types. They are also not as easily upgradeable as the desktop. Hand-Held
Is a pocket-sized computing device, typically having a display screen with touch input or a miniature keyboard. In the case of the personal digital assistant (PDA) the input and output are combined into a touch-screen interface.

Desktops
Desktops support many options and capabilities. A wide variety of cases, power supplies, hard drives, video cards, monitors and other components are available. Desktops can have many different connection types, video options, and a wide array of supported peripherals.
Desktops are commonly used to run applications such as word processing, spreadsheets and networked applications such as email and web browsing.
There is another type of computer that may look similar to a desktop, but is much more powerful: the workstation.

Workstation
Workstations are high-powered business computers. They are designed for specialized, high-end applications like engineering programs such as CAD (Computer Aided Design). Workstations are used in 3-D graphics design, video animation and virtual reality simulation. They may also be used as management stations for telecommunications or medical equipment. As with servers, workstations typically have multiple CPUs, large amounts of RAM and multiple, high-capacity disk drives that are very fast. Workstations usually have very powerful graphics capabilities and a large monitor or multiple monitors