In a layman language, a computer is a electronics device use to input data, store data, process data, retrieve data and reproduces it depending on the instructions depending on it.
A Computer System broadly consists:
* An Electronics Device
* Input Data
* Store Data
* Process Data
* Retrieve Data
* Depending on the instruction given by the user.
IT (Information Technology)
Information Technology is a part of computer science which is basically related to * Use of Computer Software
* Telecommunication Tools
Compute Science is a study of
* Computer Software
* Computer Hardware
* Related Components
Structure of Computer/Block Diagram of Computer
A computer system basically consists three devices Input Device, CPU and Output Device.
A hardware device that sends information into the CPU. Without any input devices a computer would simply be a display device and not allow users to interact with it.
Keyboard, Mouse, Joystick, Touch Screen, Light Pen, BCR, OCR, MICR etc. CPU
Abbreviation of central processing unit, and pronounced as separate letters. The CPU is the brains of the computer. Sometimes referred to simply as the processor or central processor, the CPU is where most calculations take place. In terms of computing power, the CPU is the most important element of a computer system.
It consisting of three main components: CU, Memory, ALU.
A control unit is the part of a CPU or other device that directs its operation. The outputs of the unit control the activity of the rest of the device. That portion of hardware in the CPU that directs sequence of operations, interprets coded instructions, and initiates proper commands to other parts of the computer
Storage Area/ Memory
This is the component that holds data of the Computer System. There are two types of memory available in the system: Primary Memory and Secondary Memory. Primary Memory is quick to access data and instruction. Primary Memory is much faster than reading from Secondary drive, so having a lot of RAM makes it quick to retrieve recently accessed files, applications, and other data. All programs must be run through RAM before they can be used. RAM stands for Random Access Memory. ROM (Read Only Memory) is use to store the instruction and information related to the system. RAM is volatile in nature and ROM is non-volatile.
Arithmetic Logic Unit. ALU is a generic term for a functional unit in a computer. ALUs perform various operations on data (operands) and produce an output. A simple ALU has two inputs and one output. Examples of ALU operations are ADD, SUBTRACT, SHIFT, NEGATE, AND, and OR.
Device that receive output from the computer or any peripherals that transfer or transmit data from the computer.
Monitor LCD, Speakers, printers, Plotter etc.
This type of devices is very common and mostly to perform two basic task: Input and Output or we can say available for input and output purpose.
Floppy Disk, Hard Disk, CD-ROM, DVD etc.
Characteristic of Computer
* Accuracy: Output of a computer system is 100% error free but it depends on the correctness of the entries and the program through which the system execute. Because of it, a system is known as GIGO device. GIGO means Garbage in Garbage Out. * Speed: Unlike speed of computer is measured as number of data processes in unit time. Here unit of time is so small that we can’t measure it using any general units. The special units are: * Mili Second(10-3 Second)
* Micro Second(10-6 Second)
* Nano Second(10-9 Second)
* Pico Second(10-12 Second)
* Volume: Volume of a Computer system is measured as...