Reading 1 WHAT IS A COMPUTER
ducanhtran11cdth02 > 10-13-2012, 01:23 AM
Reading 1 WHAT IS A COMPUTER?
Computers are electronic machines which can accept data in a certain form, process the data and give results of the processing in a specified format as information. They are capable of communicating with the users, of doing five kinds of arithmetic operations, and of making decision.
The three steps are involved in the process. First, the data is fed into the computer’s memory. Then, when the program is run, the computers performs a set of instructions and processes the data. Finally, we can see the results (the output) on the screen or in printed form.
Information in the form of data and programs is known as software, and the electronic and mechanical parts that make up a computer system are called hardware. A standard computer system consists of three main sections: the central processing unit (CPU), the main memory and the peripherals.
Perhaps the most influential component is the central processing unit. Its function is to execute program instructions and co-ordinate the activities of all the other units. In a way, it is the ‘brain’ of the computer. The main memory holds the instructions and data which are currently being processed by the CPU. The peripherals are the physical units attached to the computers. They include storage devices and input/output devices.
Storage devices (floppy, hard or optical disk) provide a permanent storage of both data and programs. Disk drives are used to handle one or more floppy disk. Input devices enable data to go into computer’s memory. The mpst common input devices are the mouse and keyboard. Output devices enable us to extract the finished product from the system. For example, the computers shows the output on the monitor or prints the results on the printer by means of a printer.
A. Read the text above, deciding whether the following statements are true (T) or false (F). If you feel a statement is false, change it to make it true.
1. Computers are mechanical machines which can accept, process data and give results of the processing in a specified format as information.
2. There are three steps in the process of computer.
3. The second step of processing data is to perform a set of instructions.
4. Information in the form of programs is known as software.
5. Hardware is the electronic and mechanical parts that make up a computer system.
6. CPU’s function is to execute program instructions.
7. Storage devices and input/output devices are the peripherals which are the physical units built in the computer.
8. Hard disk is a storage device that provides a permanent storage of both data and programs.
9. Data can be input in computer’s memory by means of input devices.
10. Mouse, keyboard and printer are the output devices.
B. Use the information in the text to help you match the terms in the box with the appropriate explanation or definitions below.
a. software b. peripheral devices c. monitor d. floppy disk
e. hardware f. input g. port h. output i. central processing unit
1. The brain of the computer.
2. Physical parts that make up a computer system.
3. Program which can be used on particular computer system.
4. the information which is presented to computer
5. Result produced by a computer
6. Hardware equipment attached to the computer
7. Visual display unit
8. Small device used to storage information. Same as diskette
9. any socket or channel in a computer system into which an input/output device may be connected.
Reading 2
It is common practice in computer science for the words "computer" and "processor" to be used interchangeably. More precisely, "computer" refers to the central processing unit (CPU) together with an internal memory. The internal memory or main storage, control and processing components make up the heart of the computer system. Manufacturers design the CPU to control and carry out basic instructions for their particular computer.
The CPU coordinates all the activities of the various components of the computer. It determines which operations should be carried out and in what order. The CPU can also retrieve information from memory and can store the results of manipulations back into the memory unit for later reference.
In digital computers the CPU can be divided into two functional units called the control unit (CU) and the arithmetic - logical unit (ALU).
These two units are made up of electronic circuits with millions of switches that can be in one of two states, either on or off.
The function of the control unit within the central processor is to transmit coordinating control signals and commands. The control unit is that portion of the computer that directs the sequence or step-by-step operations of the system, selects instructions and data from memory, interprets the program instructions, and controls the flow between main storage and the arithmetic - logical unit.
The arithmetic - logical unit, on the other hand, is that portion of the computer in which the actual arithmetic operations, namely, addition, subtraction, multiplication, division and exponentiation, called for in the ' instructions are performed. It also performs some kinds of logical operations such as comparing or selecting information. All the operations of the ALU are under the direction of the control unit.
Programs and the data on which the control unit and the ALU operate, must be in internal memory in order to be processed. Thus, if located on : secondary memory devices such as disks or tapes, programs and data and ftrst loaded into internal memory.
Main storage and the CPU are connected to a console, where manual control operations can be performed by an operator. The console is an important, but special purpose, piece of equipment. It is used mainly when the computer is being started up, or during maintenance and repair. Many mini and micro systems do not have a console.
A. Main idea : Which statement best expresses the main idea of the text? Why did you eliminate the other choices?
1. Main storage is not a part of the processor.
2. The CPU is made up of the control unit, the arithmetic - logical unit and internal memory.
3. The CPU is composed of the arithmetic - logical unit and control unit only.
B. Understanding the passage
Decide whether the following statements are true or false (T/F) by referring to the
information in the text.
1. The central processing unit is made up of three components.
2.The CPU is responsible for all the activities taking place within a computer.
3.The processor itself has three components.
4. The control unit directs the flow of information within the processor.
5.The arithmetic-logical unit of the processor is responsible for the interpretation of program instructions.
6.The arithmetic-logical unit is also responsible for choosing and comparing the appropriate information within a program.
7. The processor cannot operate on any information if that information is not in main storage.
8.Secondary memory and internal memory are located in the same place in the computer
system.
9. Only after the data has been processed by the CPU can results be transmitted to an output device.
10. Computers can solve problems more quickly if they operate on new information.