

Different Computer Types
There are Four Different Computer Types
We have four different computer types classified according to their performance, power, and size. A computer is an electronic device that accepts data, processes it, stores, and then produces an output.
There are different computer types available depending on the number of users they can support at any one time, their size, and power. In this hub, we are going to have a look at the difference between supercomputers, mainframe, mini, and microcomputers.
Supercomputers
Supercomputers are Very Fast and Most Powerful
1. Supercomputers – Supercomputers are very expensive, very fast, and the most powerful computers we have in the world.
Supercomputers are optimized to execute a few number of programs. This makes it possible for them to execute these few programs at a very high speed. Due to their inhibiting cost, they are used in high end places like in scientific research centers. The supercomputer consists of thousands of processors making it clock very high speeds measured by petaflops.
These computer types are also very large in size due to the numerous parts and components involved in their design.
A good example of a Supercomputer is Tianhe-2: TH-IVB-FEP Cluster; National Super Computer Center in Guangzhou, China; 3.12 million cores (33.86 petaflop/s).
A Supercomputer

Mainframe Computers
2. Mainframe computers — These are large and expensive computer types capable of supporting hundreds, or even thousands, of users simultaneously. Thus, they are mostly used by governments and large organizations for bulk data processing, critical applications, transaction processing, census, industry and consumer statistics among others. They are ranked below supercomputers.
Minicomputers
3. Minicomputers — Minicomputers are mid sized computers. In terms of size and power, minicomputers are ranked below mainframes. A minicomputer is a multiprocessing system capable of supporting from 4 to about 200 users simultaneously.
The use of the term Minicomputer has diminished and they have merged with servers.
Note: Users connects to the mainframe or minicomputers using dumb terminal – a keyboard and monitor. A dumb terminal is simply an output device that accepts data from the CPU. In contrast, a smart terminal is a monitor that has its own processor for special features, such as bold and blinking characters. Dumb terminals are not as fast as smart terminals, and they do not support as many display features, but they are adequate for most applications.
Microcomputer
4. Microcomputers or Personal computers – A personal computer is a computer designed to be used by one user at a time.The term microcomputer relates to microprocessor which is used with a personal computer for the purpose of processing data and instruction codes. These are the most common computer types since they are not very expensive.
Microcomputers Are Classified as Desktop and Portable (Mobile) Computers
Desktop Computers
Desktop computers are not built to be mobile. They are moved, but only to a new desktop location and with the power supply inactive. There are a number of major differences between computers that are intended to be used in one place as a desktop and portables or mobiles that can be easily moved from one location to another.
Desktop computers are large and heavy in comparison to portables. They can be carried in specially manufactured cases, but only to assist a support engineer in moving, not as a frequent procedure. The monitor, keyboard and mouse are all separate items on a desktop.
Desktop computer components and devices, although quite resilient to movement while active are not made to be constantly moved, even less so when they are operational. A mains power supply is mandatory, as desktop computers cannot work without a constant supply of electrical power.
The desktops can further be subdivided depending with the casing type, tower casing and desktop casing.
Tower casing
For tower casing, the motherboard is placed on side of the system unit, while the other major components like the power supply, and mass storage devices are stacked on top of each other in a cabinet. One main advantage with computers using the tower casings is that there is ample space for future upgrades for example if you wish to add more storage devices.
A Mid Tower Case

Desktop casing
For the desktop casings, the motherboard lies on the bottom and is parallel to the desk or table. The system unit is usually smaller and more compact. It is not a very good choice if you are going to install other drives like another hard disk or a DVD writer. One main advantage is that they are small and thus will occupy less space. The placement is also ideal since it will lie on top of a desk and then you can place your TFT monitor on top.
Tower or Desktop Computer?
Note: You can flip over the tower casing and end up with a desktop and you can turn your desktop to a tower literally though but the problem will be your drives will be facing sideways. So you will always have a problem inserting or removing your CDs because they will keep on falling, other drives might fail to access your CD or DVD contents due to the awkward tilted position.
Why choose a desktop?
The size of the casing determines how much space you need on your desk to place the PC. If you have a small desk with limited space, you might consider the smaller mini computer case.
There are two things that may make you consider going for tower:
a) If you have more than enough space is not an issue, then you can go for the tower casing where there are more functions.
b) If you will be adding a lot of devices to your system, for example more drives.
In terms of cost, tower casings prices are a little bit higher compared to desktops.
Portable or Mobile Computers
Portable or mobile computers are manufactured with a very important feature; they are portable (are designed for mobility). This means a computer user can be able to move with it from one point to another comfortably. One can also work from any location irrespective of if there is a power source. They:
- Are small, compact and light in weight
- Have their own power in form of a battery but of course it does not last forever, thus they have to be plugged to a source of power once in a while.
These portable devices are produced in a variety of sizes and very high processing capabilities. Good examples are Laptops, Palmtops, PDAs.
An Example of the Portable Computers
