What happens when you power on your computer?

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When a computer is turned on, a sequence of events takes place known as the boot process. Here is a detailed explanation of what happens when a computer starts:

1. Power-on self-test (POST): When the computer is turned on, the power supply sends a signal to the motherboard to start the POST process. The POST process checks the hardware components of the computer to ensure that everything is working properly. If there is an issue, an error message will be displayed.
2. BIOS: The Basic Input/Output System (BIOS) is the firmware that manages the hardware components of the computer. The BIOS is responsible for initializing and testing the hardware components, and it also stores the system configuration and boot order.
3. Boot loader: Once the BIOS completes the hardware checks, it looks for the boot loader. The boot loader is a small program that is stored in the Master Boot Record (MBR) of the hard drive. The boot loader’s job is to load the operating system into memory.
4. Operating system: Once the boot loader is loaded into memory, it loads the operating system. The operating system is the software that manages the computer’s resources and provides the user interface. During this process, the operating system loads all the necessary drivers and services.
5. User login: Once the operating system is loaded, the user is prompted to log in. The login process involves verifying the user’s credentials and loading the user’s profile.
6. Desktop: Once the user is logged in, the operating system loads the desktop environment, which includes the graphical user interface (GUI), icons, and menus. From here, the user can launch applications and perform tasks on the computer.

In summary, the boot process involves a series of steps that initialize the computer’s hardware components, load the operating system and its necessary components, and finally present the user with a login prompt and desktop environment.