Chapter 1 Computer Fundamentals

Input, Process and Output: A computer is a machine, it takes input, processes it and gives the output.

Input Devices Processing Devices Output Devices  The devices which you use to enter data and instructions into the computer are known as input devices.  Some commonly used input devices are keyboard, mouse, joystick, scanner, light pen, microphone, digital camera, trackball and touch pad.  The central processing unit (CPU), also called the microprocessor, is the processing device of a computer. It does all the calculations. It manages the working of all parts of the computer.  The CPU has three parts: Arithmetic and Logic unit (ALU), control Unit (CU) and Memory Unit (MU).  The devices which are used to get results (output) from the computer are called output devices.  Some commonly used output devices are monitor, printer, projector, plotter, speakers, headphones and headset.  The computer memory(or storage) stores the information that the CPU can access as and when required.  Different units used to measure the computer memory are bit(b), byte(B), kilobyte(KB), megabyte(MB), gigabyte(GB), terabyte(TB) and petabyte(PT).  There are two types of computer memory : primary memory and secondary memory.  Primary memory is internal memory of the computer. There are two types of primary memory: Random Access Memory(RAM) and Read Only Memory(ROM).  Secondary memory also called auxiliary memory, is used to store a large amount of information and data permanently.

Primary Memory(RAM) Secondary Memory(HDD)

Questions 1. Define a. Input Devices b. Processing Devices c. Output Devices. 2. Name two types of memories. 3. Write two examples of Input device, processing devices and output devices. 4. How the memory of computer is measured?