Lungsod ng maynila

Lungsod ng Maynila UNIVERSIDAD DE MANILA Mehan Gardens, Manila SYLLABUS Course Code: CSC 010 Course Title: Computer Fundamentals Prerequisite (if any): None Unit Course: 3 Units 1. 0 Course Description: It delves with the history and nature of computers, its developments, applications and types. It also includes the basic components of the computer system, the number systems and conversions, the elements of the Electronic Data Processing (EDP) system, the different Disk Operating System (DOS) utilities and commands, flowcharting and introduction to algorithms and programming, and the Microsoft Windows operating system. 2. 0 Course Objectives 2. 1 General Objectives: a. Apply knowledge of computer fundamentals to solve problems and perform new applications. b. Develop interest in the field of computers to be able to adjust to the demands of its trends and technology. 2. 2 Specific Objectives: a. Understand the concepts, capabilities and limitations of computers and identify its basic components. b. Convert from one number system to another number system. c. Determine the differences and advantages of the two most commonly used operating systems: DOS and Microsoft Windows operating systems. d. Familiarize with the Microsoft Windows environment, desktop, and properties. e. Know the importance of algorithm and flowcharting in preparation to programming courses. 3. 0 Course Outline: Time Allotment CHAPTER (Budgeted Time) 1. OVERVIEW AND NATURE OF COMPUTERS ………………………………………. 6 hrs. 1. History of computers and its definition 2. Characteristics, capabilities, limitations 3. Different applications and effects to society 4. Generations & classifications of computers 5. Data processing concepts 6. Reasons for computer failure 2. BASIC COMPONENTS OF THE COMPUTER SYSTEM ………………………… 6 hrs. 2. 1 Parts of the computer hardware 2. 2 Storage devices 2. 3 Input and output devices 3. ELECTRONIC DATA PROCESSING (EDP) SYSTEM…………………….. 6 hrs. 3. 1 Components, organizational structure, staff and job descriptions; 3. 2 Data communication concepts and the internet; 3. 3 Computer software types and developments 4. NUMBER SYSTEMS………………………………………………………………. 9 hrs. 4. 1 Decimal 4. 2 Binary 4. 3 Octal 4. 4 Hexadecimal 4. 5 Conversion process and techniques of the different number systems 5. DISK OPERATING SYSTEM (DOS) ……………………………………. 9 hrs. 5. 1 Booting up, system files, disk files and naming conventions 5. 2 Command prompt, error messages, tracks and sectors 5. 3 Commonly used DOS commands; Exercises 6. ALGORITHMS AND FLOWCHARTING ……………………………………. 9 hrs. 6. 1 Symbols, guidelines and exercises; 6. 2 Introduction to programming 7. MICROSOFT WINDOWS OPERATING SYSTEM………………………….. 9 hrs. 7. 1 Overview and history 7. 2 GUI, desktop components, shutting down of computer, use of mouse 7. 3 Window and its components 7. 4 Menu, dialog boxes and its components 7. 5 Settings and programs; Exercises in Windows 4. 0 Teaching Methods/Strategies: 4. 1 Lecture and discussion 4. 2 Problem-solving and exercises 4. 3 Individual/Group report 4. 4 Laboratory discussion and exercises 5. 0 Requirements: 5. 1 Diskette(s) 5. 2 Attendance 5. 3 Seat works — written and laboratory 5. 4 Quizzes, recitations/reports 5. 5 Assignments, case studies 5. 6 Major exams 6. 0 Grading System: Midterm Grade: 60% Class Standing + 40% Major Exam Pre-Final Grade: 60% Class Standing + 40% Major Exam Final Grade: Midterm Grade (50%) + Pre-Final Grade (50%) CHAPTER I OVERVIEW AND NATURE OF COMPUTERS 6 hrs. 1. History of computers and its definition 2. Characteristics, capabilities, limitations 3. Different applications and effects to society 4. Generations & classifications of computers 5. Data processing concepts 6. Reasons for computer failure INTRODUCTION Let us begin with the word ‘ compute’. It means ‘ to calculate’. We all are familiar with calculations in our day-to-day life. We apply mathematical operations like addition, subtraction, multiplication, etc. and many other formulae for calculations. Simpler calculations take less time. But complex calculations take much longer time. Another factor is accuracy in calculations. So man explored with the idea to develop a machine, which can perform this type of arithmetic calculation faster, and with full accuracy. This gave birth to a device or machine called ‘ computer’. The computer we see today is quite different from the one made in the beginning. The number of applications of a computer has increased, the speed and accuracy of calculation has increased. You must appreciate the impact of computers in our day-to-day life. Reservation of tickets in Air Lines and Railways, payment of telephone and electricity bills, deposits and withdrawals of money from banks, business data processing, medical diagnosis, weather forecasting, etc. are some of the areas where computer has become extremely useful. However, there is one limitation of the computer. Human beings do calculations on their own. But computer is a dumb machine and it has to be given proper instructions to carry out its calculation. This is why we should know how a computer works. WHAT IS A COMPUTER? Computer is an electronic device. As mentioned in the introduction it can do arithmetic calculations faster. But as you will see later it does much more than that. It can be compared to a magic box, which serves different purpose to different people. For a common man computer is simply a calculator, which works automatic and quite fast. For a person who knows much about it, computer is a machine capable of solving problems and manipulating data. It accepts data, processes the data by doing some mathematical and logical operations and gives us the desired output. Therefore, we may define computer as a device that transforms data. Data can be anything like marks obtained by you in various subjects. It can also be name, age, sex, weight, height, etc. of all the students in your class or income, savings, investments, etc., of a country. Computer can be defined in terms of its functions. It can i) accept data ii) store data, iii) process data as desired, and iv) retrieve the stored data as and when required and v)print the result in desired format. HISTORY OF COMPUTERS History of computer could be traced back to the effort of man to count large numbers. This process of counting of large numbers generated various systems of numeration like Babylonian system of numeration, Greek system of numeration, Roman system of numeration and Indian system of numeration. Out of these the Indian system of numeration has been accepted universally. It is the basis of modern decimal system of numeration (0, 1, 2, 3, 4, 5, 6, 7, 8, 9). Later you will know how the computer solves all calculations based on decimal system. But you will be surprised to know that the computer does not understand the decimal system and uses binary system of numeration for processing. We will briefly discuss some of the path-breaking inventions in the field of computing devices. Manual Mechanical Device is a simple mechanism powered by hand. Basically, these devices required some sort of physical effort from the user when used. Examples are: Fingers, stones or sticks were used to represent digits in earlier days Abacus was the first manual processing device. The device has a frame with wires and beads which slide on the wires to represent and manipulate numeric values Napier’s Bones. John Napier was Scottish mathematician who became famous for his invention of Logarithm Tables in 1614 Oughtred’s Slide Rule. This was developed by William Oughtred in 1622 and it is based on the concepts of logarithms. It performs multiplication and division by sliding a rule against fixed calibrations. Pascal Calculator. In 1645, Blaise Pascal, a French mathematician develops and builds a calculating machine that was capable of adding and subtracting numbers. The was operated by dialing a series of wheels to addd and subtract numbers containing up to eight digits. Leibniz’s Calculator. In 1674, Gottfried Wilhelm Von Leibniz made improvements on Pascal Calculator. With Leibniz improvements, it utilized the same techniques for addition ad subtraction as Pascal Calculator but could also perform multiplication and division, as well as extract roots. Babbage’s Analytical Engine. Charles Babbage, a nineteenth century Englishman, is frequently considered as the father of modern computer. He foresaw a machine that can perform all mathematical calculations, store values in its memory and perform logical comparisons among values. He called it Analytical Engine. This machine was never built because it lacks one thing — electronics. Lady Ada Byron — the first programmer Electromechanical device is usually powered by an electric motor and uses switches and relays. Example is the: Hollerith’s Punched-Card Machine. A step toward automated computation was the introduction of punched cards, which were first successfully used in connection with computing in 1890 by Herman Hollerith working for the U. S. Census Bureau. He developed a device which could automatically read census information which had been punched onto card. Surprisingly, he did not get the idea from the work of Babbage, but rather from watching a train conductor punch tickets. As a result of his invention, reading errors were consequently greatly reduced, work flow was increased, and, more important, stacks of punched cards could be used as an accessible memory store of almost unlimited capacity; furthermore, different problems could be stored on different batches of cards and worked on as needed. Hollerith’s tabulator became so successful that he started his own firm to market the device; this company eventually became International Business Machines (IBM). Electronic Device such as a modern digital computer, has its principal component circuit boards, transistors or silicon chip, and the like. EARLY COMPUTERS The Atanasoff-Berry Computer (ABC) was the first electronic digital computing device. Conceived in 1937, the machine was capable of solving up to 29 simultaneous linear equations and was successfully tested, though its input/output mechanism was still unreliable in 1942 when its inventors left Iowa State College for World War II assignments. The ABC pioneered important elements of modern computing, including binary arithmetic and electronic switching elements, but its special-purpose nature and lack of a changeable, stored program distinguish it from modern computers. ABC inventor John Vincent Atanasoff’s computer work was not widely known until rediscovered in the 1960s, amidst conflicting claims about the first instance of an electronic computer. The ENIAC computer is usually considered to be the first computer in the modern sense, but in 1973 a U. S. District Court invalidated the ENIAC patent and concluded that the ABC was the first ” computer” The IBM Automatic Sequence Controlled Calculator (ASCC), called the Mark I by Harvard University, was the first large-scale automatic digital computer in the USA. It is considered by some to be the first universal calculator. The electromechanical ASCC was devised by Howard H. Aiken, created at IBM, shipped to Harvard in February 1944, and formally delivered there on August 7, 1944. The main advantage of the Mark I was that it was fully automatic–it didn’t need any human intervention once it started. It was the first fully automatic computer to be completed. It was also very reliable, much more so than early electronic computers. It is considered to be ” the beginning of the era of the modern computer” and ” the real dawn of the computer age”. The building elements of the ASCC were switches, relays, rotating shafts, and clutches. It was built using 765, 000 components and hundreds of miles of wire, amounting to a size of 51 feet (16 m) in length, eight feet (2. 4 m) in height, and two feet deep. It had a weight of about 10, 000 pounds (4500 kg). The basic calculating units had to be synchronized mechanically, so they were run by a 50 foot (15 m) shaft driven by a five-horsepower (4 kW) electric motor. The Mark I could store 72 numbers, each 23 decimal digits long. It could do three additions or subtractions in a second. A multiplication took six seconds, a division took 15. 3 seconds, and a logarithm or a trigonometric function took over one minute. COMPUTER GENERATIONS The history of computer development is often referred to in reference to the different generations of computing devices. Each generation of computer is characterized by a major technological development that fundamentally changed the way computers operate, resulting in increasingly smaller, cheaper, more powerful and more efficient and reliable devices. Read about each generation and the developments that led to the current devices that we use today. Stored-Program Concept. Programs like data, are stored in the computer. These stored programs makes the computer “ automatic”. Once the program is loaded, the stored-program instructions are executed, thus no further human intervention is needed. This concept was introduced by John Von Neumann in 1945 and laid the foundation for the development of modern electronic computers. First Generation – 1940-1956: Vacuum Tubes The first computers used vacuum tubes for circuitry and magnetic drums for memory, and were often enormous, taking up entire rooms. They were very expensive to operate and in addition to using a great deal of electricity, generated a lot of heat, which was often the cause of malfunctions. First generation computers relied on machine language to perform operations, and they could only solve one problem at a time. Input was based on punched cards and paper tape, and output was displayed on printouts. Examples of these computers are: ENIAC: It was the first electronic computer built in 1946 at University of Pennsylvania, USA by John Eckert and John Mauchy. It was named Electronic Numerical Integrator and Computer (ENIAC). The ENIAC was 30 50 feet long, weighed 30 tons, contained 18, 000 vacuum tubes, 70, 000 registers, 10, 000 capacitors and required 150, 000 watts of electricity. Today your favorite computer is many times as powerful as ENIAC, still size is very small. EDVAC: It stands for Electronic Discrete Variable Automatic Computer and was developed in 1950. The concept of storing data and instructions inside the computer as introduced here. This allowed much faster operation since the computer had rapid access to both data and instructions. The other advantages of storing instruction were that computer could do logical decision internally. The design for the EDVAC was developed before the ENIAC was even operational. It was intended to resolve many of the problems created by the ENIAC’s design. Like the ENIAC, the EDVAC was built for the U. S. Army’s Ballistics Research Laboratory at the Aberdeen Proving Ground by the University of Pennsylvania. The ENIAC designers Eckert & Mauchly were joined by John von Neumann and some others and the new design was based on von Neumann’s 1945 report, First Draft of a Report on the EDVAC. EDSAC: Electronic Delay Storage Automatic Calculator was an early British computer (one of the first computers to be created). The machine, having been inspired by John von Neumann’s seminal EDVAC report, was constructed by Professor Sir Maurice Wilkes and his team at the University of Cambridge Mathematical Laboratory in England. EDSAC was the world’s first practical stored program electronic computer, although not the first stored program. UNIVAC: The UNIVAC (UNIVersal Automatic Computer) was the first commercial computer made in the United States. It was designed principally by J. Presper Eckert and John Mauchly, the inventors of the ENIAC. Design work was begun by their company, Eckert-Mauchly Computer Corporation, and was completed after the company had been acquired by Remington Rand. The first UNIVAC was delivered to the United States Census Bureau on March 31, 1951 and was dedicated on June 14th that year. The fifth machine (built for the U. S. Atomic Energy Commission) was used by CBS to predict the result of the 1952 presidential election. Second Generation – 1956-1963: Transistors Transistors replaced vacuum tubes and ushered in the second generation of computers. The transistor was invented in 1947 but did not see widespread use in computers until the late 50s. The transistor was far superior to the vacuum tube, allowing computers to become smaller, faster, cheaper, more energy-efficient and more reliable than their first-generation predecessors. Though the transistor still generated a great deal of heat that subjected the computer to damage, it was a vast improvement over the vacuum tube. Second-generation computers still relied on punched cards for input and printouts for output. Examples of these computers are: Third Generation – 1964-1971: Integrated Circuits The development of the integrated circuit was the hallmark of the third generation of computers. Transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers. Instead of punched cards and printouts, users interacted with third generation computers through keyboards and monitors and interfaced with an operating system, which allowed the device to run many different applications at one time with a central program that monitored the memory. Computers for the first time became accessible to a mass audience because they were smaller and cheaper than their predecessors. Some of the computers developed during this period were IBM-360, ICL-1900, IBM-370, and VAX-750. Fourth Generation – 1971-Present: Microprocessors The microprocessor brought the fourth generation of computers, as thousands of integrated circuits were built onto a single silicon chip. What in the first generation filled an entire room could now fit in the palm of the hand. The Intel 4004 chip, developed in 1971, located all the components of the computer – from the central processing unit and memory to input/output controls – on a single chip. In 1981 IBM introduced its first computer for the home user, and in 1984 Apple introduced the Macintosh. Microprocessors also moved out of the realm of desktop computers and into many areas of life as more and more everyday products began to use microprocessors. As these small computers became more powerful, they could be linked together to form networks, which eventually led to the development of the Internet. Fourth generation computers also saw the development of GUIs, the mouse and handheld devices. Fifth Generation – Present and Beyond: Artificial Intelligence Fifth generation computing devices, based on artificial intelligence, are still in development, though there are some applications, such as voice recognition, that are being used today. The use of parallel processing and superconductors is helping to make artificial intelligence a reality. Quantum computation and molecular and nanotechnology will radically change the face of computers in years to come. The goal of fifth-generation computing is to develop devices that respond to natural language input and are capable of learning and self-organization. CHARACTERISTICS, CAPABILITES AND LIMITATIONS Computer Capabilities Speed. The computer can process data transfer faster than any other machine to perform a similar task. Repetitiveness. A computer can tirelessly perform the same operation millions of times in exactly the same way without “ getting bored” the way a human would do. Accuracy. The computer can produce data with speed and repetition with great correctness and precision. Logical Operations. The computer can make decisions based on alternative courses of action. However these decisions are dependent on the choices we humans prepare. Store and Recall Information. Like the human brain, the computer can store instructions, facts and information and doesn’t forget it just like us human. It can also retrieve vast amount of data and information fast when needed. Self-Checking. The computer checks its own work for accuracy by means of parity check. Computer Limitations Incapability to Generate Information. The computer cannot generate information by its own. It can process data and information by its own but it needs a programmer to prepare the instructions. Incapability to Correct Errors. A computer is dependent to the prepared instruction by the programmer. Computers given wrong instruction will basically erroneous information. Any correction must be done by a programmer. Incapability to Make Original Decisions. A computer can perform logical operations but limited based only to the prepared alternative paths by the programmer. Incapability to Develop Meaning from Objects. A computer can’t respond to living objects. It doesn’t have feelings. Whatever meanings the computer develops are only provided by the programmer. Computer Characteristics Fast. As you know computer can work very fast. It takes only few seconds for calculations that we take hours to complete. Accurate. Hence, in addition to speed, the computer should have accuracy or correctness in computing. The degree of accuracy of computer is very high and every calculation is performed with the same accuracy. The accuracy level is determined on the basis of design of computer. The errors in computer are due to human and inaccurate data. Diligent. A computer is free from tiredness, lack of concentration, fatigue, etc. It can work for hours without creating any error. If millions of calculations are to be performed, a computer will perform every calculation with the same accuracy. Due to this capability it overpowers human being in routine type of work. Versatile. It means the capacity to perform completely different type of work. You may use your computer to prepare payroll slips. Next moment you may use it for inventory management or to prepare electric bills. Power of Remembering. Computer has the power of storing any amount of information or data. Any information can be stored and recalled as long as you require it, for any numbers of years. It depends entirely upon you how much data you want to store in a computer and when to lose or retrieve these data. No IQ. Computer is a dumb machine and it cannot do any work without instruction from the user. It performs the instructions at tremendous speed and with accuracy. It is you to decide what you want to do and in what sequence. So a computer cannot take its own decision as you can. No Feeling. It does not have feelings or emotion, taste, knowledge and experience. Thus it does not get tired even after long hours of work. It does not distinguish between users. Storage. The Computer has an in-built memory where it can store a large amount of data. You can also store data in secondary storage devices such as floppies, which can be kept outside your computer and can be carried to other computers. CLASSIFICATION OF COMPUTERS Classification According to Purpose General Purpose Computer – A device that manipulates data without detailed, step-by step control by human hand and is designed to be used for many different types of problems and applications. Special Purpose Computer -These computers are intended for specific applications. Operations of the systems are intended to a specific operation. Classification According to Data-Handled Analog Computer – It is a form of computer that uses electrical, mechanical or hydraulic phenomena to model the problem being solved. More generally an analog computer is basically measuring devices capable of converting a physical quantity into symbolic representation. Digital Computer — These machines have memory and are capable of performing complex calculations. They are not capable of obtaining data by measuring thus it needs to gather information from the user. Hybrid computers – These computers that comprise features of analog computers and digital computers. It combines the measuring capabilities of the analog computer and the logical and control capabilities of digital computers. Classification According to Capacity Supercomputer – They are the fastest and most expensive machines. They have high processing speed compared to other computers. They have also multiprocessing technique. One of the ways in which supercomputers are built is by interconnecting hundreds of microprocessors. Supercomputers are mainly being used for whether forecasting, biomedical research, remote sensing, aircraft design and other areas of science and technology. Examples of supercomputers are CRAY YMP, CRAY2, NEC SX-3 and CRAY XMP. Mainframes – Often colloquially referred to as Big Iron, are computers used mainly by large organizations for critical applications, typically bulk data processing such as census, industry and consumer statistics, ERP, and financial transaction processing. They operate at very high speed, have very large storage capacity and can handle the work load of many users. They are generally used in centralized databases. They are also used as controlling nodes in Wide Area Networks (WAN). Minicomputers – A midsized computer. In size and power, minicomputers lie between workstations and mainframes. In the past decade, the distinction between large minicomputers and small mainframes has blurred, however, as has the distinction between small minicomputers and workstations. It is a largely obsolete term for a class of multi-user computers which make up the middle range of the computing spectrum, in between the largest multi-user systems and the smallest single-user systems. Workstations – A type of computer used for engineering applications (CAD/CAM), desktop publishing, software development, and other types of applications that require a moderate amount of computing power and relatively high quality graphics capabilities. Workstations usually offer higher performance than is normally seen on a personal computer, especially with respect to graphics, processing power, memory capacity and multitasking ability. Microcomputer – Although there is no rigid definition, a microcomputer is most often taken to mean a computer with a microprocessor as its CPU. Another general characteristic of these computers is that they occupy physically small amounts of space. Although the terms are not synonymous, many microcomputers are also personal computers. Laptop Computer. – It is also notebook computer or notebook, is a small mobile computer, which usually weighs 2. 2-18 pounds, depending on size, materials, and other factors. Laptops usually run on a single main battery or from an external AC/DC adapter which can charge the battery while also supplying power to the computer itself. Personal Digital Assistants – These are handheld computers that were originally designed as personal organizers. PDAs are also known as pocket computers or palmtop computers. DATA PROCESSING CONCEPTS Data – It is distinct pieces of information, usually formatted in a special way or simply defined as any collection of facts. Data Processing — It is the manipulation of data into a more useful form. Information — It is the result of processing, manipulating and organizing data in a way that adds to the knowledge of the receiver. In other words, it is the context in which data is taken. Categories of Data Processing Mechanical Data Processing — It is the manipulation of data with the use of manual procedure and mechanical equipment. It is characterized by the use of pens, pencils, multiple copy forms, carbon paper, typewriters , calculators tabulators and filing cabinets. Electronic Data Processing – It can refer to the use of automated methods to process commercial data. Typically, this uses relatively simple, repetitive activities to process large volumes of similar information with the use of computers. Data Processing Cycle Input — It is the term denoting either an entrance or changes which are inserted into a system and which activate/modify a process. It when initial data or input data are prepared in some convenient form for processing. Processing — Typically describes the act of taking something through an established and usually routine set of procedures to convert it from one form to another, as a manufacturing procedure. It is when input data are changed and combined with other information, to produce data in a more useful form. Data Processing Operations Recording — The process of transferring data onto some useful form or document. Verifying — The process of checking the recorded data for any errors. Classifying — The process of separating data into various categories. Duplicating — The process of producing another set of a form or document. Sorting — The process of arranging data in a specific order either numerically or alphabetically. Calculating — The process of performing any arithmetic manipulation of data. Summarizing and Reporting — The process of collecting of data, condensing and formulating certain conclusions from the data are represented in a meaning format. Merging — The process of putting two or more sets of data is together to form a single sorted set of data. Storing — The process of placing similar data into files for future reference Retrieving — The process of recovering stored data when needed. Feedback — The process of comparing the output and the goal set in advance Output — This is when results of the preceding processing steps are collected. Expanded Data Processing Cycle Origination — It is the process of collecting original data. Distribution — It is the distribution of output data Storage — Results are frequently placed in storage to be used as input data for further processing in a later date Areas of Data Processing Business Data Processing — It involves a large amount or volume of input data, limited arithmetical operations and relative large volume of output Scientific Data Processing — It involves a limited volume of input and many logical or arithmetic calculations. Methods of Data Processing Batch – Executing a series of noninteractive jobs all at one time. The term originated in the days when users entered programs on punch cards. They would give a batch of these programmed cards to the system operator, who would feed them into the computer. An example of batch processing is the way that credit card companies process billing. The customer does not receive a bill for each separate credit card purchase but one monthly bill for all of that month’s purchases. The bill is created through batch processing, where all of the data are collected and held until the bill is processed as a batch at the end of the billing cycle. On-line — The use of computers to undertake tasks where transactions are initiated and data entered from terminals located in the users’ offices. Common examples are the booking of airline tickets, holidays, hotels, and car hire, and transactions in building societies and some banks. Real-time — It is a method of processing wherein one must satisfy explicit bounded response time constraint to avoid failure. Example of this is an airline ticketing reservation system wherein the system must provide information fast to show the number of seats available to avoid overflowing of passengers. Distributed — It is the method of data processing wherein different task are distributed and combined to contribute to larger goal Reasons for Computer Failure Input Errors — If a user gives the computer a wrong input definitely the computer will give wrong information. Errors in instructing the computer — A computer cannot correct itself. It is dependent to the instructions given by the programmer. If it is instructed erroneously it will generate wrong information. Improper controls — Nowadays different business firms have their own computer programs. Each department has its own unique program and if a certain user from one department operates another computer from another department with a different program, he or she might make some errors due to lack of training to use that program. Communication Gap — This problem exist between programmers and the client. There circumstances that the programmer misinterprets or misunderstood the clients specifications and he/she made the program differently. There are also times that the programmer designed the program in his/her perspective and forgot the factor that the program was to be built based on clients specifications making it a non user-friendly environment. Lack of Standard — Efficient computers are based on quality. Compromising with cost or brand in computer parts may have risk on the long run. It could be thrifty in the start but when it encounters problems it might be more costly than what you have saved. Lack of Adequate Manufacturer Support — Providing warranties and online technical support are responsibilities of a manufacturer. Locating the proper service center is important when troubleshooting issues, performing upgrades and maintaining your system so it must be accessible. Providing new drivers and software updates vital so can use them on new systems. ———————– IBM 1620 IBM 1401 CDC 3600 Processing Output Input Distribution Storage Origination Input Processing Output