CLASSIFICATION OF COMPUTERS
Computers can be generally classified by size and power as follows, though there is considerable overlap:
- I. Digital Computers
- II. Analog Computers
- III. Hybrid Computers
- IV. Mainframe Computers
- V. Super Computers
1. Personal or Digital computers:
A small, single-user computer based on a microprocessor. In addition to the microprocessor, a personal computer, has a keyboard for entering data, a monitor for displaying information, and a storage device for saving data.
Personal computers first appeared in the late 1970s. One of the first and most popular personal computers was the Apple II, introduced in 1977 by Apple Computer. During the late 1970s and early 1980s, new models and competing operating systems seemed to appear daily. Then, in 1981, IBM entered the fray with its first personal computer, known as the IBM PC.
The IBM PC quickly became the personal computer of choice, and most other personal computer manufacturers fell by the wayside. One of the few companies to survive IBM's onslaught was Apple Computer, which remains a major player in the personal computer marketplace.
I. Digital Computers:
Digital Computer is capable of receiving information in a particular form and performing sequence of operations in accordance with a predetermined but variable set of procedural instructions to produce a result in the form of information or signal that means digits '0' or '1'.
1. Desktop Computers:
Many people use desktop computers at work, home, school, or the library. They can be small, medium, or large in style, and usually sit on a desk. Once you add a monitor, mouse, and a keyboard, you have what is typically known as a desktop computer.
Most desktop computers are easy to upgrade and expand, or add new parts. Another benefit of desktop computers is the cost. If you compare a desktop and a laptop with the same features, you will most likely find that the desktop computer is priced lower
2. Laptop Computers:
The second type of computer that you may be familiar with is a laptop computer, or laptops as they are often referred to. Laptops are battery AC-powered personal computers that are more portable than desktop computers, allowing you to use them almost anywhere.
Since a laptop is smaller than a desktop, it's more difficult to access the internal components. That means you may not be able to upgrade them as much as a desktop. However, it's usually possible to add more RAM or al bigger hard drive.
3. Tablet Computers:
These use a touch-sensitive screen for typing and navigation. Since they don't require a keyboard or mouse, tablet computers are even more portable than laptops. The iPad is an example of a tablet computer.
4. Mobile Phones:
Many mobile phones can do a lot of things a computer can do, such as browsing the internet or playing games. These phones are often called smartphones.
5. Game Consoles:
A game console is a specialized kind of computer that is used for playing video games. Although they are not as fully-featured as a desktop computer.
TVs: Many TVs now include applications (or apps) that let you access various types of online content. For example, you can view your Face book news feed or watch streaming movies on Netflix.
6. Workstation:
A powerful, single-user computer. A workstation is like a personal computer, but it has a more powerful microprocessor and a higher-quality monitor.
A type of computer used for engineering applications (CAD/CAM) desktop publishing, software development, and other types of applications that require a moderate amount of computing power and relatively high quality graphics capabilities.
Workstations generally come with a large, high-resolution graphics screen, at least 64 MB (megabytes) of RAM, built-in network support, and a graphical user interface. Most workstations also have a mass storage device such as a disk drive, but a special type of workstation, called a diskless workstation, comes without a disk drive. The most common operating systems for workstations are UNIX and Windows NT.
7. Mini Computer:
a multi-user computer capable of supporting from 10 to hundreds of users simultaneously.
A midsized computer. In size and power, minicomputers lie between workstations and mainframes. In the past decade, the distinction between large minicomputers and small mainframes has blurred, however, as has the distinction between small minicomputers and workstations. But in general, a minicomputer is a multiprocessing system capable of supporting from 4 to about 200 users simultaneously.
II. Analog Computers:
Analog Computers are mostly used for measuring frequently changing physical qualities like temperature, pressure, speed etc. These computers generally receive analog data as their input from mechanical divices and calibrate the results.
Ex: Temperature, heat
Analog Computers are mostly used in engineering and scientific fields.
III. Hybrid Computers:
Hybrid Computers are combination of analog and digital computers. They have the characteristics of both Computers. These are useful where calculations are to be performed on arlogous data and results are to be reported in numerical or digital form.
These computers are mostly used in Hospitals and Medical field.
Ex: ECG Machines, Blood Pressure measuring Instruments
IV. Mainframe:
A powerful multi-user computer capable of supporting many hundreds or thousands of users simultaneously.
A very large and expensive computer capable of supporting hundreds, or even thousands, of users simultaneously. In the hierarchy that starts. with a simple microprocessor (in watches, for example) at the bottom and moves to supercomputers at the top, mainframes are just below. supercomputers. In some ways, mainframes are more powerful than supercomputers because they support more simultaneous programs. But supercomputers can execute a single program faster than a mainframe. The distinction between small, mainframes and minicomputers is vague. depending really on how the manufacturer wants to market its machines.
V. Supercomputer:
An extremely fast computer that can perform hundreds of millions of instructions per second.
The fastest type of computer. Supercomputers are very expensive and are employed for specialized applications that require immense amounts of mathematical calculations. For example, weather forecasting requires a supercomputer. Other uses of supercomputers include animated graphics, fluid dynamic calculations, nuclear energy research, and petroleum exploration.
The chief difference between a supercomputer and a mainframe is that a supercomputer channels all its power into executing a few programs as fast as possible, whereas a mainframe uses its power to execute many programs concurrently.
What is PageMaker ?
