Computer Hardware

The physical elements constituting a computer system is the hardware. The monitor, keyboard, hard drive, mouse, printer and CPU are examples of hardware. You can think of hardware as devices that can be physically touched. Most hardware devices contain a circuit board, integrated circuits, and other microelectronic devices. Without the hardware, a computer would not exist, and the software would not be able to run. Hardware devices are divided into internal hardware devices and external hardware devices. A few examples of internal devices are CD, CPU, Hard Drive and Motherboard. Examples of external devices are monitor, keyboard, mouse and printer. Let us look at some of these devices:

CPU – The CPU (Central Processing Unit) controls all activities inside the computer. Basically, it performs two types of operations – arithmetic & logical. These operations are performed on input/output devices and memory devices.

Memory Devices – The CPU stores all information in the computer’s memory. Memory is of two types – RAM (Random Access Memory) & ROM (Read Only Memory). RAM is a read & write memory device. It is volatile meaning it loses its contents when power is shut off. ROM, on the other hand, is non-volatile – it retains its contents even after power is shut off. It stores all basic information of programming the other devices present inside the system as well as the POST (Power On Self Test) sequence.

Keyboard – Keyboard translates keystrokes into letters or numbers. These letters are interpreted and executed by the computer CPU.

Mouse – The mouse is a special pointer device which, when clicked provided instructions to the CPU to execute instructions depending on what was clicked. The mouse is connected to the serial port/USB.

Monitors – The monitor receives video signals from the computer video adapter card and displays the video information as pixels on the screen. CRT monitors are no longer in vogue and have been replaces by LCD and LED monitors.