How Do Computers Work

The user provides input to the computer when it is turned on. The input is provided to the computer with the help of input devices. The Input Devices forwards the request to the CPU (i.e. the Central Processing Unit). The CPU start up certain programs and turns on some hardware devices so that more inputs can be received from the user. This process is also called booting up of a computer system.

The CPU consists of 3 main Parts:

Memory Unit (MU) Control Unit (CU) Arithmetic and Logical Unit (ALU)

Control Unit is also called the Central Nervous System of the computer and the CPU itself is called the brain or heart of the computer.

Control Unit manages the flow of control.

There are three types of Memory Devices:

Internal Memory/Main Memory External Memory Cache Memory

Main Memory:

It is a semi-conductor memory used for storing programs as well as data using programs execution. It is directly accessible to the CPU.

It is divided into three types:

RAM (Random Access Memory) ROM (Read Only Memory) CACHE Memory

Arithmetic and Logical Unit:

It is fundamental Building block of the CPU. Any Arithmetic or Logical operation to be performed is performed by the ALU. Even the basic Microprocessors also contain the ALU. ALU can also be designed to calculate any operations.

Taking the example of an Internet browser if the program has started, it is ready for the instructions from the users. The user can either enter an URL (Uniform Resource Locator) or click on any saved link. The computer knows what the user wants to do. The browser then finds that address by starting the hardware devices to work and if the address entered by user is correct then the browser tells the computer to send information from web page to the computer. The webpage is then displayed to the user over the browser.

Similarly to perform any task on the computer, the same procedure follows i.e. the user provides input to the computer with the help of input devices and then the input devices forwards the request of the user to the CPU which then processes data using its three main components i.e. the Memory Unit, Control Unit and Arithmetic and Logical Unit and then after processing the data, the Control Unit (which controls all other devices) forwards the processed data i.e. the information to the output devices and is displayed to the user.