Monday, September 6, 2010

Microcomputers (Personal computers)


Microcomputers are the most common type of computers in existence today, whether at work in school or on the desk at home. The term “microcomputer” was introduced with the advent of single chip microprocessors. The term “microcomputer” itself, is now practically an anachronism.



These computers include:



Desktop computers – A case and a display, put under and on a desk.

Laptops, notebook computers and Palmtop computers – Portable and all in one case. Varying sizes, but other than smartbooks expected to be “full” computers without limitations.

Tablet PC – Like laptops, but with only a touch-screen instead of a physical keyboard.

Smartphones, smartbooks and PDAs (personal digital assistants) – Small handheld computers with limited hardware.

Programmable calculator– Like small handhelds, but specialised on mathematical work.

In-car computers (“carputers”) – Built into a car, for entertainment, navigation, etc.

Game consoles – Fixed computers specialized for entertainment purposes (computer games).

Handheld game consoles – Ditto, but small and portable.

 Minicomputers (Midrange computers)

A minicomputer (colloquially, mini) is a class of multi-user computers that lies in the middle range of the computing spectrum, in between the largest multi-user systems (mainframe computers) and the smallest single-user systems (microcomputers or personal computers). The contemporary term for this class of system is midrange computer, such as the higher-end SPARC, POWER and Itanium -based systems from Sun Microsystems, IBM and Hewlett-Packard.



Mainframe Computers

The term mainframe computer was created to distinguish the traditional, large, institutional computer intended to service multiple users from the smaller, single user machines. These computers are capable of handling and processing very large amounts of data quickly. Mainframe computers are used in large institutions such as government, banks and large corporations. These institutions were early adopters of computer use, long before personal computers were available to individuals. "Mainframe" often refers to computers compatible with the computer architectures established in the 1960s. Thus, the origin of the architecture also affects the classification, not just processing power.



Mainframes are measured in millions of instructions per second or MIPS. An example of integer operation is moving data around in memory or I/O devices. A more useful industrial benchmark is transaction processing as defined by the Transaction Processing Performance Council. Mainframes are built to be reliable for transaction processing as it is commonly understood in the business world: a commercial exchange of goods, services, or money. A typical transaction, as defined by the Transaction Processing Performance Council, would include the updating to a database system for such things as inventory control (goods), airline reservations (services), or banking (money). A transaction could refer to a set of operations including disk read/writes, operating system calls, or some form of data transfer from one subsystem to another.



Supercomputer

A supercomputer is focused on performing tasks involving intense numerical calculations such as weather forecasting, fluid dynamics, nuclear simulations, theoretical astrophysics, and complex scientific computations. A supercomputer is a computer that is at the frontline of current processing capacity, particularly speed of calculation. The term supercomputer itself is rather fluid, and today's supercomputer tends to become tomorrow's ordinary computer. Supercomputer processing speeds are measured in floating point operations per second or FLOPS. Example of floating point operation is the calculation of mathematical equations in real numbers. In terms of computational capability, memory size and speed, I/O technology, and topological issues such as bandwidth and latency, Supercomputers are the most powerful. Supercomputers are very expensive and not cost-effective just to perform batch or transaction processing. Transaction processing is handled by less powerful computer such as server computer or mainframe

No comments:

Post a Comment