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- 1. Computer competency Computer competency is defined as the demonstrated ability to use information technology. It includes the ability to use computer applications in education and in the workplace as well as the ability to use the Internet and other information technology resources safely. Chapter One Introduction to computer
- 2. Storage capacity: Computers help to save space and economy by storing very large amount of data. This saves space, money to buy paper, ink, and shelves. Speed These days, computers process tasks in very short period of time. They can accomplish tasks in Nanoseconds or less. So they can perform very repetitive activities in slice of time. Accuracy Once well programmed, computers accomplish tasks accurately. Faulty instructions for data processing may lead to faulty result. This can be described by the term known as garbage in garbage out (GIGO). 1.3 Characteristics of Computers
- 3. Reliability Reliability is the measure of performance of computers against some predetermined standard for operation without any failure. Now a day's computers are used in sensitive areas that need very high reliability. Computers are durable and extremely reliable devices. They can operate error-free over long periods of time. For example hospitals are using computers in patient diagnosis, monitoring patient operations. Flexibility Computers are quite versatile in nature. It can perform multiple tasks simultaneously with equal ease. For example, you can listen music while you are writing some text.
- 4. 1.4 Types of computers Computers also differ based on their data processing capabilities. A. Classification based on purpose General purpose:-These computers have the ability to perform a wide range of tasks. -These machines can be used for various applications, ranging from scientific as well as business applications. Special purpose:-This includes computers which are design to handle a specific problem or to perform a single task. They lacked versatility. -However, being designed for specific tasks; they can be providing the result very quickly and effectively. These computers are used for airline reservation, satellite tracking, and air traffic control.
- 5. B. Classification based on method of operation Based on the way they process data, computers are classified in to three: Analog computers They are devices which operate by measuring. They deal with continues variable. They do not compete directly with numbers; rather, they operate by measuring physical magnitude such as pressure temperature, voltage, current and etc. E.g. Thermometer, voltmeter, speedometer. Generally, they are computers designed for specific purpose. Digital Computers Unlike the analog computers, digital computers operate by counting rather than measuring. Deal with discrete variables. Digital computer is a computing device in which data is represented by discrete numerical quantities which represented by discrete voltage states (0s and 1s). E.g. Personal Computers
- 6. Hybrid Computers The best features of analog and digital computers can be combined into a single device to form a hybrid computer. It processes the information by collecting input data with analog method, converts it into digital quantities, processes the digital values and provides the output in analog form. C. Classification based on functionality Depending on the functionality (size, speed, cost and performance), computer can be divided in to four categories as described below: Microcomputers Microcomputers (often called personal computers or PCs for short) are the smallest but most important and most frequently used type of computer particularly for end users. Basically they can be grouped into three: Laptop, Palmtop and Desktop computers.
- 7. • Desktop Desktop computers are personal computers (PCs) designed for use by an individual at a fixed location. IBM was the first computer to introduce and popularize use of desktops. A desktop unit typically has a CPU (Central Processing Unit), monitor, keyboard and mouse. Introduction of desktops popularized use of computers among common people as it was compact and affordable Desktop computers have detachable(separate) parts and not easily portable or move from place to place. developed specially for the home or office user.
- 8. • Laptop is compact and portable personal computer. Is also called notebook computers /simply notebooks. Is run using batteries and connect to networks using Wi-Fi (Wireless Fidelity) chips. They also have chips for energy efficiency so that they can conserve power whenever possible and have a longer life. Palmtop: Palmtop computer is the smallest version of microcomputer which has the same size of a pocket calculator.
- 9. Minicomputer Since it is about the size of a two drawer file cabinet, its size prevents it from being easily portable as compared to microcomputers. Minicomputers cost less to buy and maintain than mainframe computers. Is a multi-user system (carries out a processing task for multiple user working on terminals). It is capable of supporting 4 to 400 simultaneous users Since it is multi-user system it is widely used in interactive application in industries, scientific laboratories, research organizations, universities and colleges etc. It is also used for real time control and engineering design work. Some widely used minicomputer are PDP 11, IBM (8000 series), and VAX 7500.
- 10. 3. Mainframes A mainframe is an ultra-high performance computer made for high volume, processor-intensive computing task. It is physically larger than micros and minis and usually has processors with faster instruction processing speeds. A mainframe computer is generally placed in a special computer room. They are also used as the center of computer networking. are computers used by organizations like banks, airlines and railways to handle millions and trillions of online transactions per second. Important features of mainframes are :- Hundreds times Faster than servers, typically hundred megabytes per second. Big in size Very expensive Use proprietary OS provided by the manufacturers In-built hardware, software and firmware security features
- 11. 4. Supercomputer The term supercomputer has been coined to describe a category of extremely powerful computer designed for high-speed processing. It is the most expansive computer designed for an intensive tasking. highly trained data processing professionals are required to operate super computers. are the fastest computers on Earth. They are used for carrying out complex, fast and time intensive calculations for scientific and engineering applications. Supercomputer speed or performance is measured in teraflops Chinese supercomputer Sunway TaihuLight is the world’s fastest supercomputer Most common uses of supercomputers include Environmental research military defense systems weather forecasting agencies large corporations like aircraft manufacturer, Oil and gas exploration
- 12. Function and application area of computers Education • Learning through games • Educational tutorials etc. Health and Medicine • Mental health researchers Science • internet based collaborative laboratory Business • sales , marketing, retailing, banking and stock trading, etc. Recreation and Entertainment • in making movies, videos, and commercials. Accounting: • Payroll preparation • Accounts payable, invoicing. Airlines and Railways: • Time Keeping, Reservation of Tickets Hospital: • To store patient, doctor and medicine information Colleges and Universities: • Students and staffs Details Maintenance, Students Attendance Calculation and all information stored regard to student