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People and computers.
What is Information and Communication technology, microchip, and digital generation, information-dependent society, Information Age, embedded computers? What does it mean to be computer- literate? What are the disadvantages of using computers?
Information and Communication Technology (ICT) is concerned with the use of computer technology in managing and processing information. People who have grown up with PCs and microchips are often called the digital generation. Informed citizens of our information-dependent society should be computer-literate, which means that they should be able to use computers as everyday problem-solving devices. Modern computers based on integrated circuits are millions to billions of times more capable than the early machines, and occupy a fraction of the space. PCs in their various forms have become icons of the Information Age. The embedded computers are found in many devices from MP3 players to aircraft and from toys to industrial robots.
disadvantages
Our society has developed technological dependence. When computers are down, our way of life breaks down: planes stop flying, telephones don't work, banks have to close.
Computers produce electronic waste, plastic cases and microchips that are not biodegradable and have to be recycled or just thrown away.
They are responsible for health problems, e.g. computer addiction, an inappropriate and excessive use of computers.
Cybercrime, crime committed with the help of computers, is creating serious problems.
Citizens may feel a loss of privacy because of unauthorized use of personal data or receiving unwanted electronic messages.
Computer parts and essentials. What main characteristics distinguish a computer from other information-processing devices? What is hardware and software? What are the three main parts and functions of hardware? Give characteristic of three groups of peripherals. What are the main functions of the computer?
There are three basic characteristics which distinguish a computer from other information-processing devices:
• A computer is completely electronic - all its functions are carried out with electrical signals.
• A computer can remember information and hold it for future use. Computers do this on a temporary basis with memory circuits and permanently with storage devices such as magnetic disk and tape.
• A computer is programmable. Unlike other devices, built to perform a single function or limited range of functions, a computer can be instructed to do whatever task we tell it to do. A typical computer consists of two parts: hardware and software. Hardware is any piece of computer equipment, electronic or mechanical parts making up the computer system that are tangible objects.
Software refers to parts of the computer which do not have a material form, such as programs, data, protocols, etc. When software is stored in hardware that cannot easily be modified (such as BIOS ROM in an IBM PC compatible), it is sometimes called " firmware " to indicate that it falls into an uncertain area somewhere between hardware and software.
There are three basic hardware sections.
1. The CPU is the most important item of hardware, the heart of the computer, a microprocessor chip at the center of the computer system which processes data, executing program instructions, and coordinates the activities of all the other units.
2. The main memory holds the instructions and data which are being processed by the processor. It has two main sections: RAM (random access memory) and ROM (read only memory). It only stores information while the computer is switched on and it has a limited capacity.
3. Peripherals are the physical units (devices) that can be attached to the computer. They include:
• Input devices, which enable data and commands to be fed into the computer memory (e.g. the keyboard and the mouse).
• Output devices, which let us extract the results from the system, usually to display the processed data (e.g. the monitor and the printer). I/O (input/output) is the means by which a computer exchanges information with the outside world. Hard Disk drives, floppy disk drives and optical disc drives serve as both input and output devices. Computer networking is another form of I/O.
• Storage devices, which are used to store both data and programs permanently (e.g. hard disks and DVD-RW drives). They have a much greater capacity than the main memory. Disk drives are used to read and write data on disks.
Functions of a PC.
The main functions any computer is designed to perform are: input, processing, output and storage.
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