Information

Classification of computer (by size, speed, cost) Micro Computer Mini Computer Main Frame Computer Super Computer (01) Micro Computer The microcomputer is also known as personal computer or simply Pc’s. A personal computer is computer that can perform all its input processing, output and storage activities by itself. A personal computer contains a processor, memory and one or more input, output and storage device. Personal computers are available in two models. These are: 1) Desktop PC’s 2) Tower PC’s (02) Mini Computer and Mid-range computer It is larger and more power full then personal computer It consists of two or more processors. Minicomputer were introduced in 1960s. The first minicomputer introduced in 1960s. The first minicomputer was introduced in the mid 1960’s by Digital Equipment Corporation (DEC). These are smaller in size have lower cost than mainframe. These computers are known as minicomputer because of their small size as computer to other computer at that time. T...

Types of Computer Computer can be divided into three categories depending upon their construction and form of input data that they accept and process. These are:  Analog Computer  Digital Computer Hybrid Computer (1) Analog Computer (Image of Analog Computer) The word “Analog” means continuously varying quantity the analog computer accept input data n continuous form and output obtained in the form of graphs it means these computers accept input and given output in the form of analog signals. The output is measured on a scale the voltage current, sound, speed, temperature, pressure etc. The analog computer has low memory size and have fewer function these are very fast in processing but output return is not very accurate these are used in industrial units to control varies processes and also used in different fields of engineering. (2) Digital Computer (Image of  Digital computer)                           ...

Important Characteristics of Computer Speed Accuracy Reliability Communication Consistency Huge Storage Speed The computer is very high speed electronic device it can perform calculation (or can process data) at very high speed. Accuracy A computer is also very accurate device. It gives accurate output result. However, the output result depends upon the correction input data and set of instruction given to computer. If input is incorrect the resulting output will be incorrect. Reliability The electronic computer in modern computation have very low failure rate. The modern computer can perform complicated calculation without creating any problem and produces consistent (reliable) result. In general, computer is very reliable. Communication Today computer is mostly used to exchange messages or data through computer networks all over the world for example, the information can be received or sent through the internet with the help of computer. Consistency People often difficulty to repeat ...

  Information Processing Cycle (IPC) Information processing cycle consists of a series of tasks or steps required to convert data in to information. Input—Entering data into the computer. Processing—Performing operat ions on the data. Storage—Saving data, programs, or output for future use. Output—Presenting the results. If Needed

Basic Components of Computer Basically a computer system involves the following. (01) Hardware (02) Software  (03) Data   (04) Information   (05) User Hardware The physical and tangible parts of computer are called hardware like keyboard, monitor, mouse and printer etc. Software The set of instruction that tells the computer “What to do and How to do. Data A collection of raw facts and figures is called data which can include text, number, images, audios, and video etc. Information The processed form of data is called information. User A person who uses computer.

Digital Storage Storage is the area where data can be kept on a permanent basis, when it is not immediately needed for processing. Digital Storage Magnetic Tape (Sequential) It is an example of old tape storage media to storage a large amount of data permanently Tape process of reading or writing of data on the tape is very Slow Data can only be accessed sequentially . Magnetic Disk It is most widely used storage media for all type of computer. Information can be recorded on or red form the Magnetic surface magnetic dais is a random access storage media. Type of Magnetic Disk These are the following types of the magnetic disk. (01) Floppy Disk 1.44 MBs (02) ZIP disk 100 MBs but have later version this to first 250 MBs and then 750 MBs. (03) Hard Disk (1 TB or 1000GB) Optical Disk CD (Compact Disk) CD is the most popular optical medium it can hold 650MBs to 800MBs of data. The data on the CD cannot be erased like magnetic diskettes. DVD (Digital Versatile Disk / Digital Video Disk) DVD ...