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What is computer?. Some feel that computers are. Too difficult to learn. Taking over their jobs. They might damage the computer. A computer is a machine that manipulates data according to a list of instructions.
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What is computer? Some feel that computers are Too difficult to learn Taking over their jobs They might damage the computer A computer is a machine that manipulates data according to a list of instructions. A computer can be defined as an electronic device that takes input from its user stores, processes data and generates the required output as per the processing instructions given to it by the user.
What it does? Computer solves the problem by performing the following activities Input: Input devices feed the computer the raw matter –facts or data. Processing: The storage of data, numerical comparisons, arithmetic operation are performed on data to produce desired results. Output: The processed data or information is sent to the output device connected to computer. General Purpose computers require the following hardware components: Central Process Unit (CPU): The ‘heart’ of computer, the component that actually executes instructions. Memory: Enables a computer to store, at least temporarily, data and programs
MassStoragedevice: Allows a computer to permanently retain large amounts of data. Common mass storage devices include disk drives and tape drives. Inputdevice: Usually a keyboard or mouse, which enters data and instructions to a computer. Output device: A display screen, printer or other such devices that lets you see what the computer has accomplished. CPU, core memory and external bus interface
General features of a computer Word Length: A digital computer operates on binary digits. [ 0 and 1] A binary digit is called a bit. A group of 8 bits is called a byte. In computing, "word" is a term for the natural unit of data used by a particular computer design. A word is simply a fixed-sized group of bits that are handled together by the machine. The number of bits in a word is called the wordsize or wordlength. Commonly used word lengths are 8, 16. 32, 64 bits Operating systems like Windows or OS/2 provide the possibility to run 16-bit (segmented) programs as well as 32-bit programs.
General features of a computer Speed: Computer can process millions of instructions per second. The speed of computers is measured in terms of microseconds(10-6), nanoseconds(10-9) and picoseconds(10-12). Ex., Supercomputer. Storage: Computer data storage, often called storage or memory, refers to computer components, devices, and recording media that retain digital data used for computing for some interval of time. Historically, memory and storage were respectively called primary storage and secondary storage. Capability of storing and retrieving huge amounts of data in a fast and efficient manner is one of the important characteristics of computers
General features of a computer Accuracy: The computers never make a mistake. The degree of accuracy provided by a particular computer depends upon its design. Errors can occur in a computer, but they are generally due to human and not the technological weaknesses. Computer follows the following technology GIGO - Garbage in Garbage out Versatility: Versatility means that computers can do variety of jobs depending upon the instructions fed to them and their hardware characteristics. Computer can perform activities ranging from simple calculation to performing modeling and simulation to navigating missiles and satellites.
General features of a computer Automation: The level of automation achieved in a computer is phenomenal. All the repetitive works can be performed by computer without any mistake and delay. Automation plays an increasingly important role in the global economy and in daily experience. Engineers strive to combine automated devices with mathematical and organizational tools to create complex systems for a rapidly expanding range of applications and human activities.
General features of a computer Diligence: Means being constant and earnest in effort and applications. Human being is suffered from weakness like tiredness, lack of concentration, etc. Human being cannot perform the same or similar tasks over and over again with the same precision, accuracy and enthusiasm as the first time.
Generation of Computers History of computing: The history of computers starts out about 2000 years ago, at the birth of the abacus, a wooden rack holding two horizontal wires with beads strung on them. When these beads are moved around, according to programming rules memorized by the user, all regular arithmetic problems can be done. A more modern abacus. Note how the abacus is really just a representation of the human fingers: the 5 lower rings on each rod represent the 5 fingers and the 2 upper rings represent the 2 hands.
Generation of Computers History of computing: Charles Babbage a mathematics professor. In 1812, Babbage realized that many long calculations, especially those needed to make mathematical tables, were really a series of predictable actions that were constantly repeated. From this he suspected that it should be possible to do these automatically. a general purpose, fully program-controlled, automatic mechanical digital computer. Babbage called this idea an Analytical Engine The machine was supposed to operate automatically, by steam power, and require only one person there. Babbage’s computers were never finished. Various reasons are used for his failure. Most used is the lack of precision machining techniques at the time. Another speculation is that Babbage was working on a solution of a problem that few people in 1840 really needed to solve. After Babbage, there was a temporary loss of interest in automatic digital computers.
Generation of Computers First-generation von Neumann machines : American mathematician who made major contributions to a vast range of fields including set theory, functional analysis, quantum mechanics, ergodic theory, , economics and game theory, computer science, numerical analysis, hydrodynamics (of explosions), and statistics, as well as many other mathematical fields. The first universal programmable computer in the Soviet Union was created by a team of scientists under direction of Sergei Alekseyevich Lebedev from Kiev Institute of Electrotechnology, Soviet Union (now Ukraine).
Generation of Computers First-generation: (1945 – 1956) The Von Neumann Architecture has become the standard for modern computer systems; most computers since then have some version of this architecture. About the first generation computer hardware: • The vacuum tube computers were very big in size • These computers use to dissipate lot of heat • Rate of failure was more as vacuum tubes burn out very frequently • Electric power consumption was very large. • The inputs and outputs was in form of 1s and 0s. • In early 1940, a computer was with 18,000 tubes and 1500 relays to move information through the machine – called Electronic numerical Integrator and Calculator. ENIAC.
Generation of Computers Second-generation: (1956 – 1963) • the vacuum tube has been replaced by solid-state semiconductor devices such as transistors and solid-state diodes • The transistor was work in the computer by 1956 which is advances in magnetic-core memory and led to 2G computers that were smaller, faster, more reliable and energy efficient than their predecessors. A vacuum tube Hi-Fi amplifier • 2G computers replaced machine language with assembly language to abbreviated programming codes to replace long, difficult binary codes.
Generation of Computers Advantage over vacuum tubes • Small size and minimum weight • No warm up period for cathode heater after power supply. • Extremely long life. Some transistorized devices produced more than 30 years ago are still in service. • Rate of failure was lesser than vacuum tubes computers • Electric power consumption was lesser than 1G • its maximum temperature is limited • it has relatively high leakage current • it cannot withstand high voltages • it is less suitable for fabricating integrated circuits • The most high level languages such as COBOL and FORTRAN came into common use during this time.
Generation of Computers Third Generation Computers (1964 – 1971) • Though transistors were clearly an improvement over the vacuum tube, they still generate heat. • There are two main advantages of ICs over discrete circuits: cost and performance • an integrated circuit is also known as IC, microcircuit, microchip, silicon chip, or chip • In later stage, more components are fit into a single chip called semiconductor. • Failure of IC was rare. • Power consumption was far lesser. • Different languages were developed.
Generation of Computers Fourth Generation Computers (1971 - Presents) • After IC, Large scale integration (LSI) could fit hundreds of components onto one chip. • VLSI (Very large scale integration) squeezed hundreds of thousands of components onto a chip. • IBM introduced its personal computer (PC). • Computers continued their trend toward a smaller size, working their way down from desktop to laptop computers to palmtop • Macintosh offered an OS that allowed users to move screen icons instead of typing instructions. • Users controlled the screen cursor using a mouse. • The technologies like LAN, networks, internet, web were developed.
Generation of Computers Fourth Generation Computers (1971 - Present) • Sophisticated languages like query languages are developed. • GUI concepts are introduced. Fifth Generation Computers (Present and beyond) • Fifth generation computers are based on Artificial Intelligent • Voice recognition, nanotechnology are upcoming trends. • The goal of fifth-generation computing is to develop devices that respond to natural language input and are capable of learning and self-organization • Natural (human) language are Kannada, Hindi, etc., • Computer language are C, C++, etc.,
Types of computers by function Analog computer: Represents changing values as continuously variable physical quantities • Example: mechanical watch, voltmeter, ammeter. When used in reference to data storage and transmission, analog format is that in which information is transmitted by modulating a continuous transmission signal, such as amplifying a signal's strength or varying its frequency to add or take away data. • For example, telephones take sound vibrations and turn them into electrical vibrations of the same shape before they are transmitted over traditional telephone lines • In general, analog computers are extraordinarily fast, since they can solve most complex equations at the rate at which a signal traverses the circuit, which is generally an appreciable fraction of the speed of light.
Types of computers by function Digital Computer: In contrast, a digital clock is capable of representing only a finite number of times (every tenth of a second, for example). • Example: Digital watch shows every second not continuous. Computers, which handle data in digital form, require modems to turn signals from digital to analog before transmitting those signals over communication lines such as telephone lines that carry only analog signals. The signals are turned back into digital form (demodulated) at the receiving end so that the computer can process the data in its digital format. • Modem is used for modulate and demodulate. • Digital computers can be built to take the solution of equations to almost unlimited precision, but quite slowly compared to analog computers
Types of computers by function Hybrid Computer: Hybrid computer measures both continuous and discrete form of data. Hybrid computers can be used to obtain a very good but relatively imprecise 'seed' value, using an analog computer front-end, which is then fed into a digital computer iterative process to achieve the final desired degree of precision For example: STD phone is combination of analog and digital. Communication is analog and charges is measured in the form of digital. ECG system in a hospital is the example for hybrid computer
Types of Computer by size and capacity PersonalComputer: A small, single user computer based on a microprocessor. Run comparatively easy to use applications software such as the word processors, excel, etc., Less sophisticated video display screens. Example: ACER, Compaq, etc
Types of Computer by size and capacity Workstation: A powerful, single user computer. A workstation is like a personal computer, but it has a more powerful microprocessor and a higher quality monitor. To run complex programs and display both work in progress and results graphically. Provides higher resolution compared to PC Processors are faster than PC Examples: Sun, Apollo, HP and IBM. However, the distinction between PC and workstations is now blurring.
Types of Computer by size and capacity Minicomputer: A multi-user computer capable of supporting 10 to hundreds of users simultaneously. Initially minicomputers are used to control machines in a manufacturing unit Also the increasing power of microcomputer workstations have it harder to distinguish between mini and workstations. Example: VAX made by Digital Equipment Corporations. Mini computers work well in what are known as Distributed Data Processing. Example: Client /Server model.
Types of Computer by size and capacity Mainframe: A powerful multi user computer capable of supporting many hundreds of users simultaneously. Mainframe computers can process several million program instructions per second. Mainframe computers are mainly used by airline, railway reservation systems, etc., It has maximum primary memory RAM 518MB secondary memory stores 4.5 million MB data. Example: IBM S/390, PDP370. These machines often run for years without interruption, with repairs and hardware upgrades taking place during normal operation
Types of Computer by size and capacity Supercomputer: An extremely fast computer that can perform hundreds of millions of instructions per second. The distinction between supercomputers and mainframes is not a hard and fast one, but supercomputers generally focus on problems which are limited by calculation speed while mainframes focus on problems which are limited by input/output and reliability ("throughput computing") and on solving multiple business problems concurrently (mixed workload). Both types of system offers parallel processing Supercomputers typically expose it to the programmer in complex manners, while mainframes typically use it to run multiple tasks. One result of this difference is that adding processors to a mainframe often speeds up the entire workload transparently.
Types of Computer by size and capacity Supercomputers are optimized for complicated computations that take place largely in memory, while mainframes are optimized for comparatively simple computations involving huge amounts of external data. For example, weather forecasting is suited to supercomputers, and insurance business or payroll processing applications are more suited to mainframes. Supercomputers are often purpose-built for one or a very few specific institutional tasks (e.g. simulation and modeling). Mainframes typically handle a wider variety of tasks (e.g. data processing, warehousing). Consequently, most supercomputers can be one-off designs, whereas mainframes typically form part of a manufacturer's standard model lineup.
Types of Computer by size and capacity Mainframes tend to have numerous ancillary service processors assisting their main central processors (for cryptographic support, I/O handling, monitoring, memory handling, etc.) so that the actual "processor count" is much higher than would otherwise be obvious. Supercomputer design tends not to include as many service processors since they don't appreciably add to raw number-crunching power. There has been some blurring of the term "mainframe," with some PC and server vendors referring to their systems as "mainframes" or "mainframe-like." This is not widely accepted and the market generally recognizes that mainframes are genuinely and demonstrably different.
Types of Computer by Speed The speed of computer measured by MHz. (mega-Hertz) Which means million cycles per second. So, a computer that has a 500MHz clock is doing something 500 million times per second. But what that something, it may be an instruction. 8086 and 8088 This can run the same programs but one could not fit into the other’s socket. Depending on the manufacturer, the 8086 and 8088 processors would run at a speed ranging from 4MHz to 16MHz.
Types of Computer by Speed Pentium The Pentium was a big step in the evolution of the processor. The major difference was that it contained more than one execution unit. An execution unit receive the instructions and activates them. Having more than one execution unit meant the processor could do more than one thing at a time. Pentium II The Pentium II, Intel totally abandoned sockets and turned to the concept of slots. Slot – I is introduced for technical reasons. The Pentium II running at the speed of 400 MHz with the fullspeed 2nd level cache.
Types of Computer by Speed Celeron The celeron was in fact a Pentium II whose 2nd level cache has been removed making it supposedly twice as slow as Pentium MMX. Xeon The xeon is a Pentium II whose 2nd level cache runs at full processor speed( a regular PII 2nd level cache runs at half the processor speed). Xeon is not slot compatible with the PII but uses a new type of slot name Slot-2. Motorola, SPARC, MIPS processors were developed by Sun Microsystems.
Computer Applications – Office Automation Office automation refers to the varied computer machinery and software used to digitally create, collect, store, manipulate, and relay office information needed for accomplishing basic tasks and goals The backbone of office automation is a LAN, which allows users to transmit data, mail and even voice across the network Office cannot be automated in the same way the factory was automated. Office tasks involve a great deal of thinking and decision-making. ERGONOMICS Any knowledge worker regardless of background can easily useable. This is called ergonomics, the study of how to create safety, comfort and ease to use.
Computer Applications – Office Automation Text Management systems All documentation work come under text management. Example: letters, memos, circular, preprinted forms, reports, envelopes, labels etc., Business analysis Systems A decision support system helps the knowledge worker to extract information from the various MIS database and reporting systems, analyze it, and then formulate a decision for business planning An executive support system is an information system that consolidates and summarizes ongoing transitions within the organization. Network and Communication systems The communication media are phone, computer, fax, email, teleconferencing and voices message systems.
Computer Applications – Industry and Engineering A programmable logic controller (PLC) or programmable controller is a digital computer used for automation of industrial processes, such as control of machinery on factory assembly lines. Unlike general-purpose computers, the PLC is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact Electronic Data Interchange (EDI) EDI is the computer-to-computer exchange of business documents in a standard format. The format look much like standard forms though highly structured. Project Management When projects from marketing campaigns to construction projects are undertaken, keeping track of all the tasks is a big job and that is what project management. Project Management One concept they use is the critical path: the series of tasks that must follow one another in order and cannot overlapped.
Computer Applications – Healthcare and Education Health informatics or medical informatics is the intersection of information science, computer science, and health care. Computers are used for multi-purpose tasks such as diagnosing the disease, capture and transmit photographs of internal problems such as blood clots and tumors that previously can be seen only during exploratory surgery, monitoring patients at their bedside. In addition, computers are so tiny that they can be swallowed are proving to be valuable diagnostic tool.
Computer Applications – Graphics and Multimedia Not too long ago, the term multimedia referred to room having slide projectors, overhead projectors, tape decks and movie projectors. Multimedia presentations were hard to put together and even harder to run. Today, multimedia is widely used in the entertainment and education fields. Multimedia has entered the mainstream because of its capabilities to attract people and to hold their attention and more effective than an ordinary presentation. • Multimedia Tools • Paint and draw • Bitmap images • Vector graphics (also 3D) • Animation • Morphing • Anti-aliasing (smoothes the edges) • Multimedia can be used for • Entertainment, • Corporate presentations • Education training • Simulation • Digital publications,.. Morphing-blends two images to create a third. Starting with photographs of a young girl and an elderly woman.
