513 - 1: UNDERSTANDING COMPUTER SYSTEM

1. SKILL AREA 513: REVIEW COMPUTER SYSTEMS 513 - 1: UNDERSTANDING COMPUTER SYSTEM

2. WHAT IS A COMPUTER? an electronic device that manipulates information, or "data.“ has the ability to store, retrieve, and process data; • use a computer to type documents, send email, and browse the internet. • use it to handle spreadsheets, accounting, database management, presentations, games, and more.

3. WHAT IS A COMPUTER SYSTEM THEN? It 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.

4. History of computers 1. First Generation (1940-1956) Vacuum Tubes 2. Second Generation (1956-1963) Transistors 3. Third Generation (1964-1971) Integrated Circuits 4. Fourth Generation (1971-Present) Microprocessors 5. Fifth Generation (Present and Beyond) Artificial Intelligence

5. First Generation (1940-1956) Vacuum Tubes • Used vacuum tubes for circuitry and magnetic drums for memory • Often enormous, taking up entire rooms. • Very expensive to operate, use a great • deal of electricity, generated a lot of heat, • which was often the cause of malfunctions. • Relied on machine language, the lowest-level programming language under stood by computers, 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. • The UNIVAC and ENIAC computers are examples of • first-generation computing devices.

6. Second Generation (1956-1963) Transistors • Transistors replaced vacuum tubes. • The transistor was far superior to the • vacuum tube, allowing computers to • become smaller, faster, cheaper, more • energy-efficient and more reliable. • Though the transistor still generated a great deal of heat, it was a vast improvement over the vacuum tube. • Still relied on punched cards for input and printouts for output. • Second-generation computers moved from cryptic binary machine language to symbolic, or assembly languages, which allowed programmers to specify instructions in words. • The first computers that stored their instructions in their memory, which moved from a magnetic drum to magnetic core technology.

7. 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 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.

8. 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. • 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.

9. 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. • Used in parallel processing • Used superconductors • Used in speech recognition • Used in intelligent robots • Used in artificial intelligence

10. Classification of computers By principles of operation By size

11. By PRINCIPLES OF OPERATION: • 1. Analog • 2. Digital • 3. Hybrid

12. ANALOG Analog computers work on the principle of measuring; - measurements obtained are translated into data. Modern analog computers usually employ electrical parameters, such as voltages, resistances or currents, to represent the quantities being manipulated. Such computers do not deal directly with the numbers. They measure continuous physical magnitudes.

13. DIGITAL - Digital computers operate with information, numerical or otherwise, represented in a digital form. • Such computers process data into a digital value • (in 0s and 1s). • - performs calculations and logical operations with quantities represented as digits, usually in the binary number system - They give the results with more accuracy and at a faster rate.

14. HYBRID - For computational purposes, hybrid computers use analog components and for storage, digital memories are used. - Hybrid computers incorporate the measuring feature of an analog computer and counting feature of a digital computer.

15. By SIZE: • 1. Supercomputers • 2. Mainframes • 3. Mini computers • 4. Micro computers

16. SUPERCOMPUTERS Used for highly calculation intensive tasks and problems requiring complex calculations such as weather forecasting, climate research, molecular modeling, aircraft and spacecraft designing, etc. Fastest and most powerful computers – generally operate 4 to 10 times faster than mainframe computers At the frontline of current processing capacity, particularly speed of calculation Designed to work on a single problem at a time

17. MAINFRAME COMPUTERS The chief difference between a supercomputer and a mainframe is that a supercomputer channels all its power into executing a few programs as fast as possible, whereas a mainframe uses its power to execute many programs concurrently. In some ways, mainframes are more powerful than supercomputers because they support more simultaneous programs. But supercomputers can execute a single program faster than a mainframe. Very large and powerful computers – enormous input, process, output and storage capacities Generally used in centralized databases. Mainframe computers are able to host multiple operating systems and can handle hundreds of users simultaneously

18. MINI COMPUTERS In general, a minicomputer is a multiprocessing system capable of supporting from 4 to about 200 users simultaneously. Midsized computers whose size, speed and capabilities lie somewhere between mainframe and microcomputer. They are used for real-time applications in industries, research centers, etc. The users can access the minicomputer through their PCs or terminal.

19. MICRO COMPUTERS A microcomputer contains a central processing unit (CPU) on a microchip (the microprocessor), a memory system , a bus system and I/O ports, typically housed in a motherboard. a complete computer on a smaller scale also known as personal computer or PC a computer designed for an individual

20. MICRO COMPUTERS Laptop Desktop Netbook Handheld Tablet Workstation Wearable computers Server

21. DESKTOP • A PC that is not designed for portability is a desktop computer. • Most desktops offer more power, storage and versatility for less cost than their portable brethren.

22. LAPTOP • Laptops, also known as notebooks, are small-sized portable computers can be placed on the lap and used there. The display, hard drive, keyboard, memory, processor, and a trackball or point device are integrated in a battery-operated package.

23. NETBOOK • Ultra-portable computers that are even smaller than traditional laptops. • Cheaper than almost any brand-new laptop but, netbooks' internal components are less powerful than those in regular laptops.

24. HANDHELD • A portable computer that is small enough to be held in one's hand. • The most popular hand-held computers are those that are specifically designed to provide PIM (personal information manager) functions, such as a calendar and address book.

25. TABLET • A tablet computer, or simply tablet, is a one-piece mobile computer. • Devices typically have a touchscreen, with finger or stylus gestures replacing the conventional computer mouse. • Often supplemented by physical buttons or input from sensors • An on-screen, hideable virtual keyboard is usually used for typing. • Tablets differentiate themselves by being larger than smart phones or personal digital assistants.

26. WORKSTATION It is simply a desktop computer that has a more powerful processor, additional memory and enhanced capabilities for performing a special group of task, such as 3D Graphics or game development.

27. SERVER • A computer, or series of computers, that link other computers or electronic devices together that provides data to other computers. • Serve data to systems on a local area network (LAN) or a wide area network (WAN) over the Internet. • Many types of servers exist; web servers, mail servers, file servers.

28. WEARABLE COMPUTERS • Computers that are worn on the body. • This type of wearable technology has been used in behavioral modeling, health monitoring systems, information technologies and media development. • Especially useful for applications that require computational support while the user's hands, voice, eyes, arms or attention are actively engaged with the physical environment.