COMPUTER HARDWARE AND SOFTWARE
Concept: Parts Working Together
A computer system is a system of interconnected computers that share a central storage system and various peripheral devices such as a printers, scanners or routers. Each computer connected to the system can operate independently, but has the ability to communicate with other external devices and computers. A computer system functions effectively only when all these components perform their assigned task. The failure of any one component of the system leads to the failure of the whole system. A computer system is not an individual device but a collection of number of physical parts. The physical parts that make up the entire computer system is called a computer hardware.
A typical personal computer consists of the following physical parts: input device, output device, microprocessor, computer memory, system board, expansion port, expansion slots and cards, and computer power supply. The computer hardware is involved in the performance of data processing. Advanced version of these basic parts is used to create multimedia systems, which can integrate text, graphics, animation, sound and video.
Input is any information the computer collects from the outside world. The input can be in the form of text, programs, commands and user responses. The device that collects the input and sends it to the computer is called an input device. There are a variety of input devices, which are used by computers. Input devices include keyboard, pointing devices, scanners, web camera, digital camera, audio and video input devices. Input devices carry out the following functions: a It accepts data from the outside world. b. It converts this data into the binary form. 0 It sends data in binary form to the CPU for further processing.
Note:- Multimedia systems are built according to standards set by the Multimedia PC (MPC) Working Group, a collection of hardware and software companies. The MPC Level 3 that requires that multimedia systems which should have a powerful Pentium processor with at least 8 MB of RAM.
Output Devices The derivation of the final result as meaningful information for the user after processing is called output. It can appear in a variety of forms such as text, graphics, audio and video. The device that supplies information and sends the results of computation to the outside world is called an output device. The most common output devices are computer monitors and printers. Output devices carry out the following functions:
- It accepts the data in binary form from the computer.
- It converts coded data into human readable form.
- It supplies the converted results to the outside world.
Microprocessor is a power source of personal computer. It is the center of all processing activities. It is an integrated circuit on a tiny silicon chip that contains thousand or millions of tiny on/off switches, known as transistors. The type of microprocessor contained in the computer determines how much and how quickly data can be processed The microprocessor is the “brain” of the system. It has two basic components: control unit and arithmetic-logic unit.
How microprocessor works
The control unit is the nerve centre of the computer. The control unit of the centra processing unit regulates and integrates the operations of the computer. It directs the movement of electronic signals between memory (which temporarily holds data instructions and processed information) and the arithmetic-logic unit. It also directs thes control signals between the CPU, and input and output devices.
The arithmetic-logic unit, usually called the ALU, performs two types of operation arithmetic and logical. Arithmetic operations are the fundamental math operation addition, subtraction, multiplication and division. Logical operations consist comparisons i.e. two pieces of data are compared to see whether one is equal to (E), les than (<), or greater than (>) the other. The ALU uses registers to hold data that is bein processed.
In 1971, Intel introduced the world’s first microprocessor-the Intel 4004. The company has produced a steady stream of new processor models, beginning with the 8088 processor that powered the original IBM PC.
The computer memory is an essential component of a computer system. Computer memory are the internal storage areas in a computer that are used to temporarily or permanently store data or instructions to be executed. Computer memory can be divided into the following iwo types: primary memory and secondary memory.
Primary memory is a computer memory that is directly accessible to the central processing unit of a computer. It operates at a very high speed and can be accessed directly by the Central Processing Unit. The primary memory of a computer system is made up of a set of memory chips. There are two types of memory chips. Each type of memory chip is used for a different purpose in a computer system. They are: Random Access Memory and Read Only Memory.
Random Access Memory(RAM)
Random Access Memory (RAM) is a type of computer memory that an be accessed randomly; that is, any byte of memory can be accessed out touching the preceding bytes. It is used to store the information instructions that operate the computer’s programs. Typically, rams are transferred from storage on a disk drive to RAM. RAM is also known as volatile memory because the information within the computer chips is lost when power to the computer is turned off.
Read Only Memory (ROM)
Read Only Memory is a type of data storage device which is manufactured with fixed Fontents. It contains special instructions called the ROM BIOS (Basic Input/Output System) for detailed computer operations. These instructions tell the computer how to access the hard disk, find the operating system, and load it into RAM. It is housed in a single integrated circuit which is plugged into the motherboard. It is read-only memory which means that the CPU can read, or retrieve, the programs written on the ROM chip. However, the user cannot write or change the information or instructions in ROM. The contents of the ROM are written into at manufacturing time. It is non-volatile in nature, meaning that its contents are not lost when power supply is switched off.
Cache memory (pronounced as “cash memory”) is a small, high-speed memory system that temporarily stores frequently used instructions and data for quicker processing by the central processor of a computer. It is placed in between the CPU and RAM. It is used to store the most frequently accessed information stored in RAM. When the processor needs to read from a location in the main memory, it first checks whether a copy of that data is in the cache; if it is, the processor immediately uses this copy, which is much faster.
Secondary Memory The secondary memory is a long-term memory used to store programs and data for the future reference. It supplements the limited storage capacity and the volatile characteristics of primary memory. This is because secondary memory is much cheaper than primary storage, and the data or programs stored in secondary memory will not be lost when electrical power is switched off. It is also known as backing storage or external memory Some of the common examples of secondary memory are hard disk, floppy disk, CD DVD, pen drive, etc.
Concept: Putting Machine to Life
Computer has no intelligence and it cannot do anything on its own. The hardware alone does not do much of anything. It needs clear cut instructions to solve a problem or carry out a task. A set ofdetailed, step-by-step instructions that tells a computer how to solve a problem or carry out a task is called a computer program
A group of such programs that are put into a personal computer to operate and control its activities is called the software. It performs input operations, processes the data and outputs the results. Without the instructions provided by software, computer hardware is unable to perform any of the tasks we associate with computer.
There are different kinds of software, each of which serves a specified purpose. These Hollware are broadly classified into two categories, namely system software and application software. Computer software is a collection of computer programs that provide instructions telling a computer what to do and how to do it. Computer software are sets of programs, algorithms, procedures and its documentation.
System Software Nystem software is the chief manager of the computer system. It is the set of one or more programs that are basically designed to control the computer hardware and to give a platform for running application software. It serves as an intermediary between hardware
and application software. It makes the operation of the computer system more effective and efficient. It consists of four kinds of programs: operating system software, utility programs, device drivers and language translators.
Operating system is the most important software that runs on a computer. It manages the computer’s memory, processes, and all of its software and hardware. It also owes you to communicate with the computer without knowing how to speak the computer’s “language.” Modern computer operating systems are becoming increasingly machine-independent, capable of running on any hardware platform. Microsoft Windows, Linux and Mac OS are some of the most popular operating systems. Without an operating system, a computer is useless.
Utility Program software is a computer software designed to help in the management and tuning of operating systems, computer hardware and application software. It performs a specific