Booting:

    Booting is a process or set of operations that loads and hence starts the operating system, starting from the point when user switches on the power button.


Boot Loader:

    A boot loader is a type of program that loads and starts the boot time tasks and processes of an operating system or the computer system.

It enables loading the operating system within the computer memory when a computer is started or booted up.

A boot loader is also known as a boot manager.

Booting Sequence:
       
Boot sequence is the order in which a computer searches for nonvolatile data storage devices containing program code to load the operating system .

Typically, a Macintosh structure uses ROM and Windows uses BIOS to start the boot sequence.

Once the instructions are found, the CPU takes control and loads the OS into system memory.

The devices that are usually listed as boot order options in the BIOS settings are hard disks, floppy drives, optical drives, flash drives, etc.

The user is able to change the boot sequence via the CMOS setup. Boot sequence is also called as boot order or BIOS boot order.

The Booting Sequence is Follows:

   
     Turn on the Power button.
        
    CPU pins are reset and registers are set to specific value.
        
     CPU jump to address of BIOS (0xFFFF0).
        
     BIOS run POST (Power-On Self Test) and other necessary checks.
        
     BIOS jumps to MBR(Master Boot Record).
        
     Primary Bootloader runs from MBR and jumps to Secondary Bootloader.
        
     Secondary Bootloaders loads Operating System.

These are the tasks that are carried during booting process.