Difference between BIOS and Kernel

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    Kernel is one of the most important part of Operating System. We use the word kernel to mean the part of operating system that runs in the privileged mode (Sometimes even a subset of this). Kernel is closer to the hardware and often performs tasks like memory management and system calls.

    Now for BIOS (Basic Input-Output System), it is the one which is responsible to provide drivers for new devices to OS. BIOS constitutes of the code that is stored in read-only memory (ROM) and some configuration data in non-volatile RAM.
    BIOS provides three primary functions:

    1. Power on self test (POST), so it knows where to load the boot program.
    2. Load and transfer control to boot program .
    3. Provide drivers for all devices.

    The main BIOS is supplied as a chip on the motherboard. It contains everything needed to perform the above three functions. Additional BIOSes on other boards can provide access to additional devices.

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    BIOS is before kernel, which works like a bootloader

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    I think you may be little bit confused about BIOS and Boot loader.
    Both are working together but their tasks should be different. Technically BIOS should be explained..
    the task of the boot loader is have to find the boot file of the operating systems and initiate the boot file to load the operating system.

    I think you can understand this..

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    Agree with you.

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    BIOS is before kernel, which works like a bootloader

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    Bios is the basic output input system of the computer which means it the most basic program that runs on the computer and the first one as well, it allows you to configure hardware configurations, diagnose problems and etc. Whereas the kernel is the heart of the operating system (not the computer) it's purpose is to bridge between the hardware and user mode applications. The kernel is overall mostly used to make operating systems more stable and to prevent the operating system from crashing because of one dumb process.

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    Let's first trying to define and understand BIOS and Kernel.


    BIOS stands for "Basic Input/Output System", in old machines, the firmware was known as the BIOS, but more modern systems use UEFI (The Unified Extensible Firmware Interface) now, which is faster and more general and makes better use of facilities in contemporary processors.


    The one program running at all times on the computer. It is the core of a computer's OS, with complete control over basically everything in the system. Typically, it is responsible for memory management, process management and disk storage management. It is the middle layer between system hardware and applications.

    BIOS vs Kernel

    For a computer to start running, for instance, when you power it up, it needs to have an initial program to run. This little simple "initial program" is also called "bootstrap program", typically is stored within the computer hardware in ROM (Read-only memory) or EEPROM (Electrically erasable programmable read-only memory), known by the general term firmware, now if you connect the BIOS definition we defined earlier, you should have a good understanding of what BIOS is. The firmware (BIOS) initializes all aspects of the system, from CPU registers to device controllers to memory contents. Then it locates the kernel and load it into a protected area of memory for running.

    Hope my answer helps.

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    BIOS is in hardware level , but kernel is a little higher and run upon it.
    Before the system is up,BIOS will firstly check the CPU,memory socket,and then load the kernel to run

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