Introduction Of Computer System!!

 

Computer:The word computer is derived from the latin word computer which means 'to count' 'to calculate' 'to sum up' or 'two things together'. An electronic device which accepts input  from the users, process it according to the instructions given to it and give the required result in the form of output, is a computer.

Computer system
   A computer can process data images, audio, video and graphics. A computer performs five major operations of functions irrespective of their size and make. They are
1)It accepts data or instruction by way of input.
2) It stores data.
3) It can process data as required by the users.
4) It gives result in the form of output.
5) It controls all operation inside a computer.

Architecture of computer
Computer architecture is and specification detail of how is said of software and hardware technology standards interact to form a computer system.In short Computer architecture refer to how a computer system is design and how it works.





Every computer system has the following three basic components:
1] input unit
2] central processing unit
3] output unit

1) Input unit: This you need help user to enter data and command into a computer system. Data can be in the form of numbers, words, action, command, etc.The main function of input device is to direct command and data into a computer. Computer then uses its CPU to process data and produce output.
For example, a keyboard is an input device that enters number and characters. Similarly, even a mouse can be an input device for entering directions and commandsother examples include barcode reader, magnetic ink character reader (MICR), optical character reader (ocr),etc.
Another example of input device is touch screens. Users can simply touch the screen without using any other device and enter commands. From smartphone to ATM machines coma this input device are becoming very popular nowadays.

2) Central Processing Unit (CPU):
after receiving data and commands from users a computer system has to process sheet according to the instructions provided.
Here, it has to relay on a component called the central processing .The CPU for the uses this 3 elements


A] Arithmetic and  logic unit:This part of CPU perform arithmetic operations. It does basic mathematical calculations like addition, subtraction, division, multiplication,etc. Futher, it can even perform logical functions like the comparison of data.

B] Control Unit: This unit is the backbone of the computers. It is responsible for coordinating task between all components of a computer system.The control unit collects data from the input unit and send it to the processing unit depending on its nature. Finally, it for the transmits data to output unit to facilitate users.

C] Memory Unit:Once a user enters data using input device in the computer system stores this data in the memory unit. This data will not remain here until the other components of CPU processor it.The memory unit uses a set of Pre-programmed instructions to the further transmit this data to other parts of the CPU.

Types of memory- there are two types of memory
1]Primary memory
2]Secondary memory
1)Primary memory: primary memory is internal memory of a computer. It is also known as main memory. primary memory holds the data and instruction on which computer is currently working.
Types of primary memory- primary memory is generally of two types
1)RAM
2)ROM
 

1]RAM(RANDOM ACCESS MEMORY):it stand for random access Memory. RAM is known as read / write memory. It is generally referred as the main memory of the computer system. It is a temporary memory. The information stored in the memory is lost as the power supply of the computer is switch off. That's why RAM is also known as "volatile memory."
2]ROM(READ ONLY MEMORY):It stand for read only memory. ROM is a permanent type of memory. The content is not loss when the power supply is switched off. Content of ROM is decided by the computer manufacturer and permanently stored at the time of manufacturing.ROM cannot be overwritten by a computer. It is called "non-volatile memory"

2) Secondary Memory: it is an external memory  of the computer. It is used to store the huge amount of different programs and information.
The secondary storage device are:
1] Magnetic (Hard) Disc.
2] Magnetic Tapes.
3] Pen Drive.
4] Flash Memory.
5] Optical Disc (CD, DVD).
6] SSD etc.

3) Output Unit:The third and final component of a computer system is the output unit. After processing the data, it is converted into a format which human can understand. After conversion, the output unit displays this data to users. Example of output devices include monitors, screen printers and speakers etc. Thus, output unit basically reproduce the data formatted by the computer from the user's benefit.