Booting in operating system is a process that initiates the starting of a computer. It executes a set of instructions that is present in the ROM (BIOS). These instructions perform a power self-test that identifies if all the hardware of the system is perfectly fine, and along with this, it loads the operating system in the main memory of the system.
Booting is the process that takes place in every computer system. It hardly takes a few minutes. Let’s learn more about the process in the section ahead.
Booting in Operating System
- What is Booting Process?
- Why do we Require Booting?
- Types of Booting
- What is Dual Booting?
- Bootable Devices
What is a Booting Process?
Booting specifies a process that takes place when we switch on our computer system. When we turn the power button on, we just supply power to the system. this power reaches the motherboard and its components and invokes them to play their part in the entire working of the computer system.
Now here, the BIOS, which is one of the components of the motherboard, start playing its part. We have discussed BIOS in our previous content, ‘Motherboard of Computer’. BIOS is a Basic Input Output System. The BIOS performs the POST, i.e., Power on Self-Test and reports if there occurs any problem in the hardware present in the system.
After performing POST successfully, the BIOS start displaying some of the details about the system, such as:
- Name of BIOS manufacturer
- RAM information etc.
With this, the BIOS handover the control to the master boot code (MBC). MBC is the information stored in the first sector of your hard drive. MBC identifies the location of the operating system in the hard drive. Then the boot manager loads the operating system on the RAM. And thus, the operating system becomes the first program that is loaded into the main memory.
Why is Booting Required?
Well, we know that booting is a process that loads the operating system into the main memory. And the operating system is the only program that manages all the other application programs that are present on your computer system.
Types of Booting in Operating System
If we talk about the booting process, we can differentiate it into two types, as discussed below:
When you start your computer from the start, i.e., straight away from the point where you switch on the power button and supply power to the system. We refer to it as cold booting. Cold booting performs the entire process that we discussed above. We also refer to cold booting as hard booting.
Warm booting is also referred soft booting. The warm booting takes place when the computer starts from no response or hang state. Here the computer is already in a power-on state. We also refer to this condition as rebooting.
The rebooting may take place due to various reasons such as:
- We reboot the system when we install any new software.
- We perform any changes in the system settings.
What is Dual Booting?
We know that it is possible to operate two or multiple operating systems on a single computer. So, when a computer with two operating systems boots up, we refer to it as dual booting.
But if your computer has multiple operating systems on a single bootable device, then the system displays a menu from which the user has to select the operating system he wants to work on. And if no choice is made, the system itself loads the default operating system.
What is Bootable Device?
A bootable device is one from which the BIOS loads the operating system into the main memory of your computer. The bootable devices can be a:
- Internal hard drive
- Optical drive
- Floppy drive
- External hard drive
- USB device
- Network interface card
How can we have multiple operating systems on a single bootable device?
To store multiple operating systems on a single bootable device, it is partitioned into multiple segments. Here each partition stores a different operating system. And when the system boots up, the user can select which operating system he wants to load onto the main memory.
So, we conclude that booting in operating system is the process that loads OS onto the main memory of the computer. We have two kinds of booting, i.e., cold booting and warm booting.
Cold booting takes place when we start the system right from supplying power to the system. warm booting takes place when we reboot our system. We have also discussed the term dual-booting which occurs when your bootable device has two operating systems.