These days, computers are available in many sizes and types. Some computers can fit in the palm of the hand and some can occupy the entire room. Computers also differ based on their data processing abilities. Based on the physical size, performance, and application areas, we can generally divide computers into four major categories: micro, mini, mainframe, and supercomputers.
A microcomputer is a small, low-cost digital computer, which usually consists of a microprocessor, a storage unit, an input channel, and an output channel, all of which may be one chip inserted into one or several PC boards. The microcomputer is generally the smallest of the computer family. Originally, these were designed for individual users only but nowadays they have become powerful tools for many businesses that, when networked together, can serve more than one user.
IBM-PC Pentium 100, IBM PC Pentium 200, and Apple macintosh are some of the examples of microcomputers. Microcomputers include desktop, laptop, and handheld models such as PDAs(personal digital assistants)
A mini-computer is a small digital computer, which normally is able to process and store less data than a mainframe but more than a microcomputer, while doing so less rapidly than a mainframe but more rapidly than a microcomputer. It is about the size of a two-drawer filing cabinet. Generally, It is used as desktop devices that are often connected to a mainframe in order to perform the auxiliary operations.
Minicomputer is designed to meet the computing needs of several people simultaneously in a small to the medium-sized business environment. It is capable of supporting from 4 to about 200 simultaneous users. Some of the widely used mini-computers are PDP 11, IBM(8000 series), and VAX 7500.
A mainframe is an ultra-high-performance computer made for high-volume, processor-intensive computing. It consists of a high-end computer processor, with related peripheral devices, capable of supporting large volumes of data processing, high-performance online transaction processing systems. Moreover, it is designed to perform at a faster rate than a mini-computer and at an even faster rate than a microcomputer.
Mainframes are the second largest(in capability and size) of the computer family. Examples of mainframe computers are IBMs E8000, and CDC 6600.
Supercomputers are special purpose machines, which are specially designed to maximize the numbers of FLOPS(floating-point operation per second). Any computer below one gigaflop/ sec is not considered a supercomputer. A supercomputer has the highest processing speed at a given time for solving scientific and engineering problems. Essentially it contains a number of CPUs that operate in parallel to make it faster.
Its processing speed lies in the range of 400- 10,000 MFLOPS(millions of floating-point operations per second). Due to this feature, supercomputers help in many applications including information retrieval computer-aided design.
A supercomputer can process a great deal of information and make extensive calculations very quickly. It can resolve complex mathematical equations in a few hours, which would have taken a scientist with paper and pencil a lifetime, or years, using a hand calculator. It is the fastest, costliest, and most powerful computer available today. Typically, supercomputers are used to solve multi-variant mathematical problems of existent physical processes, such as aerodynamics, metrology, and plasma physics.
These are also required by the military strategies to stimulate defense scenarios. Cinematic specialists use them to produce sophisticated movie animations. Scientists build complex models and stimulate them in a supercomputer. However, supercomputers have limited broad-spectrum use because of their price tag and limited market. The largest commercial uses of supercomputers are in the entertainment/advertising industry. CRAY-3, cyber 205, and PARAM are some well-known supercomputers.