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Boot sequence

(also boot order, BIOS boot order)

Boot sequence definition

It's a routine a computer follows upon startup. It first checks vital components like memory. Then, a machine searches for its main storage, like a hard disk or a solid-state drive. After that, a computer finds the essential system software and loads it. Performing this sequence ensures the computer is ready for use.

See also: master boot record, warm boot, bootloader, secure boot

Use cases of a boot sequence

  1. 1.System updates. A device must restart after installing a critical software update or system patch. The boot sequence ensures the new updates integrate properly with the existing system during startup.
  2. 2.Hardware diagnostics. If a technician suspects a hardware issue with a computer, they might reboot the device. During the boot sequence, any failures in essential components can be detected, aiding in diagnostics.
  3. 3.New hardware integration. A computer typically needs a restart when installing a new piece of hardware, such as a graphics card or memory module. The boot sequence helps in initializing and integrating the new hardware with the system.
  4. 4.System recovery. In cases where a system might have crashed or become unresponsive, a forced restart initiates the boot sequence. This process helps load a stable operating system version and potentially fix any temporary glitches.
  5. 5.Dual booting. The boot sequence plays a pivotal role for computers configured to run multiple operating systems. Upon startup, users can choose which OS to load, and the boot sequence ensures the selected system starts up correctly.