第1个回答 2007-12-25
The computer is under instructions to accept input, processing input data and produce electronic information equipment. There are four types of computers: Microcomputer, Minicomputer, mainframe and supercomputer.
Computer can solve a series of problems, and do hundreds or even thousands of logic judgement without feeling tired and fatigue. In a small part of it can find the answers in time. Computer can be monotonous and routine tasks instead of people, but they are not far invasive; it in accordance with its instructions to work without any value judgement. However, the computer can be a lot of instantaneous arithmetic / logic operations.
Small computer, also known as medium-sized machine, as the size of desk machines, their processing speed and data storage capacity ranging from between the microprocessor and supercomputers. Medium-sized companies and departments of large companies generally use them for special purposes. For example, you can use them for research or monitoring of a production process. Small companies generally use Minicomputer an overall data processing, for example, statistics.
Macintosh Software only run on a Macintosh computer, which provides high-quality graphical user interface and is very easy to use, the Apple Macintosh system 7.5 Motorla is for the use of the PowerPC microprocessor APPLE computer design, Apple is a machine important milestone, they like Windows NT and OS / 2, is a powerful operating system. System 7.5 with network functions, and allowed to deliver. Windows and OS / 2 documents it has several advantages
Data communication systems through communication lines to transmit data from one place to another place in the electronic system, you can use the data communications through your computer to send news and information to users of the other machines friends, you may work for a company , its computer systems throughout a building, or even the whole world. That is, all part of - input and output modules, processors, and storage devices - in different places, through the communication link. Or you might use long-distance communication lines, telephone lines, located close to the external data unit information. Then you could transmit information to their own PC to work for and analysis.
Data communications circuits can be connected to the preparation of two: point-to-point and multi-point line connections. Point-to-point circuits connect directly to send and receive equipment, and multi-point line connecting multiple devices, and equipment is not just a sender and a receiver equipment.
Satellite communications refers to the use of the orbit of a satellite transmission from the station to the information to one or more other stations. Communications satellite communications is the area of research results, the objective is to obtain the lowest possible price range and the ever-increasing capacity.
Asynchronous data to be transmitted or synchronized. In asynchronous transfer mode, one can only send and receive a self-section is Microcomputer often the methods used. ATM is often used to slow the final broken equipment. The advantage is a convenient sender can transmit data. The disadvantage is that the relatively slow data transfer rate. Transmitted for a few bytes sent or block the transmission of large amounts of information. In order to achieve data transfer, the sender and recipient of nodal must be a precise time interval. Therefore, the system requires a synchronous clock. The advantage is data can be quickly transmitted disadvantage is the need for the necessary equipment.