Introduction to Computer Hardware PDF

Information Technology  Introduction to Computer Hardware The term “Computer” is derived from the Latin word “Compute”, which means to calculate. A computer is an electronic machine, devised for performing calculations and controlling operations that can be expressed eithe...

Information Technology  Introduction to Computer Hardware The term “Computer” is derived from the Latin word “Compute”, which means to calculate. A computer is an electronic machine, devised for performing calculations and controlling operations that can be expressed either in logical or numerical terms. In simple terms, a computer is an electronic device that performs diverse operations with the help of instructions to process the information in order to achieve the desired results. The computer is a device that transforms data into meaningful information. Data can be anything like marks obtained by you in various subjects. It can also be the name, age, sex, weight, height, etc. of all the students in a class. A computer is an electronic device, operating under the control of instructions stored in its own memory that can accept data (input), process the data according to specified rules, produce information (output), and store the information for future use. Functionalities of a computer Any digital computer carries out five functions in gross terms: 1. Input: Entering data and instructions into the computer 2. Storage: Saving data, programs and documents 3. Processing: Performing calculations and operations on inputted data 4. Output: Displaying processed information to the user 5. Control: Coordinating hardware components to properly execute input, processing, output and storage tasks Characteristics of a Computer ❖ High Speed The computer is a very fast device. It is capable of performing calculations of very large amounts of data. The computer has units of speed in microseconds, nanoseconds, and even picoseconds. It can perform millions of calculations in a few seconds as compared to a man who will spend many months performing the same task. ❖ Accuracy In addition to being very fast, computers are very accurate. The calculations are 100% error-free. Computers perform all jobs with 100% accuracy provided that the input is correct. ❖ Storage Capability Memory is a very important characteristic of computers. A computer has much more storage capacity than human beings. It can store large amounts of data. It can store any type of data such as images, videos, text, audio, etc. ❖ Diligence Unlike human beings, a computer is free from monotony, tiredness, and lack of concentration. It can work continuously without any error and boredom. It can perform repeated tasks with the same speed and accuracy. ❖ Versatility A computer is a very versatile machine. A computer is very flexible in performing the jobs to be done. This machine can be used to solve problems related to various fields. At one instance, it may be solving a complex scientific problem, and the very next moment it may be playing a card game. ❖ Reliability A computer is a reliable machine. Modern electronic components have long lives. Computers are designed to make maintenance easy.  ❖ Automation Computer is an automatic machine. Automation is the ability to perform a given task automatically. Once the computer receives a program i.e., the program is stored in the computer memory, then the program and instruction can control the program execution without human interaction. ❖ Reduction in Paper Work and Cost The use of computers for data processing in an organization leads to reduction in paper work and results in speeding up the process. As data in electronic files can be retrieved as and when required, the problem of maintenance of large number of paper files gets reduced. Though the initial investment for installing a computer is high, it substantially reduces the cost of each of its transaction. Applications of Computers A computer has high speed of calculation, diligence, accuracy, reliability, or versatility which has made it an integrated part of all business organizations. A computer is used in business organizations for Payroll calculations Budgeting Sales analysis Financial forecasting Managing employee database Maintenance of stocks, etc. Banking Today, banking is almost totally dependent on computers. Banks provide the following facilities − Online accounting facility, which includes checking current balance, making deposits and overdrafts, checking interest charges, shares, and trustee records. ATM machines which are completely automated are making it even easier for customers to deal with banks. Insurance Insurance companies are keeping all records up-to-date with the help of computers. Insurance companies, finance houses, and stock broking firms are widely using computers for their concerns. Insurance companies are maintaining a database of all clients with information showing − Procedure to continue with policies Starting date of the policies Next due installment of a policy Maturity date Interests due Survival benefits Bonus Education The computer helps in providing a lot of facilities in the education system. The computer provides a tool in the education system known as CBE (Computer Based Education). CBE involves control, delivery, and evaluation of learning. Computer education is rapidly increasing the graph of number of computer students. There are a number of methods in which educational institutions can use a computer to educate students. It is used to prepare a database about the performance of a student and analysis is carried out on this basis. Marketing In marketing, uses of the computer are following Advertising − With computers, advertising professionals create art and graphics, write and revise copy, and print and disseminate ads with the goal of selling more products. Home Shopping − Home shopping has been made possible through the use of computerized catalogues that provide access to product information and permit direct entry of orders to be filled by the customers. Healthcare Computers have become an important part in hospitals, labs, and dispensaries. They are being used in hospitals to keep the record of patients and medicines. It is also used in scanning and diagnosing different diseases. ECG, EEG, ultrasounds and CT scans, etc. are also done by computerized machines. Following are some major fields of health care in which computers are used. Diagnostic System − Computers are used to collect data and identify the cause of illness. Lab-diagnostic System − All tests can be done and the reports are prepared by computer. Patient Monitoring System − These are used to check the patient's signs for abnormality such as Cardiac Arrest, ECG, etc. Pharma Information System − Computer is used to check drug labels, expiry dates, harmful side effects, etc. Surgery − Nowadays, computers are also used in performing surgery. Engineering Design Computers are widely used for Engineering purpose. One of the major areas is CAD (Computer Aided Design) that provides creation and modification of images. Some of the fields are − Structural Engineering − Requires stress and strain analysis for design of ships, buildings, budgets, airplanes, etc. Industrial Engineering − Computers deal with design, implementation, and improvement of integrated systems of people, materials, and equipment. Architectural Engineering − Computers help in planning towns, designing buildings, determining a range of buildings on a site using both 2D and 3D drawings. Military Computers are largely used in defence. Modern tanks, missiles, weapons, etc. Military also employs computerized control systems. Some military areas where a computer has been used are Missile Control Military Communication Military Operation and Planning  Smart Weapons Communication Communication is a way to convey a message, an idea, a picture, or speech that is received and understood clearly and correctly by the person for whom it is meant. Some main areas in this category are E-mail Chatting Usenet FTP Telne Computers Generations Generation in computer terminology is a change in technology a computer is/was being used. Initially, the generation term was used to distinguish between varying hardware technologies. But nowadays, generation includes both hardware and software, which together make up an entire computer system. Following are the main five generations of computers: FIRST GENERATION The period of the first generation was 1946-1959. The first generation of computers started with using vacuum tubes as the basic components for memory and circuits for the CPU (Central Processing Unit). These tubes like electric bulbs produced a lot of heat and were prone to the frequent fusing of the installations, therefore, were very expensive and could be afforded only by very large organizations. In this generation, mainly batch-processing operating systems were used. In this generation, Punched cards, Paper tape, and Magnetic tape Input & Output devices were used. There were machine codes and electrically wired board languages used. The main features of First Generation are: Vacuum tube technology Unreliable Supported Machine language only Very costly Generate lot of heatSlow Input / Output device Huge size Need of A.C. Non-portable Consumes a lot of electricity 8 Some computers of this generation were: ENIAC EDVAC UNIVAC IBM-701 IBM-650 SECOND GENERATION The period of second generation was 1959-1965. This generation using the transistor was cheaper, consumed less power, more compact in size, more reliable and faster than the first generation machines made of vacuum tubes. In this generation, magnetic cores were used as primary memory and magnetic tape and magnetic disks as secondary storage devices. In this generation, assembly language and high-level programming language like FORTRAN, COBOL was used. There was Batch processing and Multiprogramming Operating system used. The main features are: Use of transistors Reliable as compared to First generation computers (FGC) Smaller size as compared to FGC Generate less heat as compared to FGC Consumed less electricity as compared to FGC Faster than FGC Still very costly A.C. needed Support machine and assembly languages Some computers of this generation were: IBM 1620 IBM 7094 CDC 1604 CDC 3600 9 UNIVAC 1108 THIRD GENERATION The period of third generation was 1965-1971. The third generation of computer is marked by the use of Integrated Circuits (IC's) in place of transistors. A single IC has many transistors, resistors and capacitors along with the associated circuitry. The IC was invented by Jack Kilby. This development made computers smaller in size, reliable and efficient. In this generation, Remote processing, Time-sharing, Real-time, Multi- programming Operating System were used. High-level language (FORTRAN-II TO IV, COBOL, PASCAL PL/1, BASIC, ALGOL- 68, etc.) were used during this generation. The main features of Third Generation are: IC used More reliable Smaller size Generate less heat Faster Lesser maintenance Still costly A.C. needed Consumed lesser electricity Support high-level language Some computers of this generation were: IBM-360 series Honeywell-6000 series PDP(Personal Data Processor) 10 IBM-370/168 TDC-316 FOURTH GENERATION The period of the Fourth Generation was 1971-1980. The fourth generation of computers is marked by the use of Very Large Scale Integrated (VLSI) circuits. VLSI circuits having about 5000 transistors and other circuit elements and their associated circuits on a single chip made it possible to have microcomputers of the fourth generation. Fourth-generation computers have become more powerful, compact, reliable, and affordable. As a result, it gave rise to the personal computer (PC) revolution. In this generation, Time sharing, Real-time, Networks, and Distributed Operating Systems were used. All the higher-level languages like C and C++, DBASE, etc., were used in this generation. The main features of the Fourth Generation are: VLSI technology used Very cheap Portable and reliable Use of PC's Very small size Pipeline processing No A.C. needed The concept of the internet was introduced Great developments in the fields of networks Computers became easily available Some computers of this generation were: DEC 10 STAR 1000 PDP 11 11 CRAY-1 (Super Computer) CRAY-X-MP (Super Computer) FIFTH GENERATION The period of the Fifth Generation is 1980-till date. In the fifth generation, the VLSI technology became ULSI (Ultra Large Scale Integration) technology, resulting in the production of microprocessor chips having ten million electronic components. This generation is based on parallel processing hardware and AI (Artificial Intelligence) software. AI is an emerging branch in computer science which interprets means and methods of making computers think like human beings. All the higher level languages like C and C++, Java,.Net, etc., are used in this generation. Artificial Intelligence includes: Robotics Neural networks Game Playing Development of expert systems to make decisions in real life situations. Natural language understanding and generation. The main features of Fifth Generation are: ULSI technology Development of true artificial intelligence Development of Natural language processing Advancement in Parallel Processing & Superconductor technology More user friendly interfaces with multimedia features Availability of very powerful and compact computers at cheaper rates Some computers types of this generation are: Desktop 12 Laptop NoteBook UltraBook ChromeBook 13