A computer is an electronically programmed machine which is able to carry out logical or mathematical operations automatically without the need for manual intervention. Modern computers are able to do general sets of operations such as word processing or simple logic operations. These operations were previously performed by a human operator using a keyboard and mouse. However, computers are increasingly used in many other aspects of modern business.


In computer studies, a logical operation is one in which there is no possibility of a memory error or a program collision. An example of such an operation is multiplication. A logical operation on a logical computer will always result in an addition (computation) or a subtraction (data removal) operation. On a hybrid computer, a logical operation is one in which a partial memory error is acceptable and in which partial data removal is possible. In a completely logical operation, partial memory errors will always result in partial results.

Most people are aware of the differences between analog computer systems and digital computer systems. They are also aware of the analog computer being slower than a digital computer because it has to use more circuitry to accomplish each result. Digital machines, however, are significantly faster than an analog machine because they do not have to use as much circuit to accomplish each result. Digital machines also typically use less power than an analog computer and are therefore far more energy efficient.

Supercomputers are much faster than any of the previous examples and therefore they are generally used to perform highly complicated calculations. Examples of such highly complex calculations are the calculation of elliptical mathematically or to solve certain optimization problems. Examples of supercomputers which are used in specialized applications are the neural network supercomputers which are used in intelligence systems and computer graphics. One computer which is used in specialized applications is the supercomputer at Los Alamos National Laboratory. This supercomputer is called JE Warren and it is a joint project between the United States and Russia.

A Minicomputer, as a general term, is a miniaturized personal computer which is manufactured as a desktop computer. A Minicomputer is different from a Minivault because it is not a virtual machine. Virtual machines are those that emulate many other types of devices, but a Minicomputer is meant to run directly on mainframe computers. The mainframe is a type of computer that is highly parallel but has its own input and output devices which are in the form of mainframes. It has several processors but unlike a VSM it does not have virtualization. The reason a Minicomputer is smaller than a virtual machine is because the operating system is not on the mainframe but on the individual computers.

The most advanced and popular type of personal computer is the multitasking computer. These types of computers are so powerful that they can perform many tasks at the same time. Some of these computers are so powerful that they are referred to as supercomputers. There are some multi-user computers which are not actually used by users but are used by IT technicians for diagnostic purposes or for storing data.