What Is UEFI, and How Is It Different from BIOS?

UEFI (Unified Extensible Firmware Interface) and BIOS (Basic Input/Output System) are both firmware interfaces that provide an interface between the operating system and the hardware of a computer. However, there are significant differences between the two.

BIOS has been the standard firmware interface for PCs since the 1980s. It is a basic firmware interface that initializes and tests hardware components during the boot process and then loads the operating system. It uses a 16-bit processor mode and is limited in the amount of storage space available, making it difficult to add new features.

UEFI is a newer firmware interface that was developed to replace BIOS. It uses a 64-bit processor mode, which enables it to support more modern hardware, such as larger hard drives and faster boot times. UEFI also provides a more advanced interface for configuration and management of hardware components, such as storage devices, network interfaces, and input/output devices.

Here are some of the key differences between UEFI and BIOS:

  1. Boot Process: BIOS loads the operating system from the Master Boot Record (MBR) on the hard drive, while UEFI loads the operating system from the EFI System Partition (ESP).
  2. Interface: BIOS has a simple text-based interface, while UEFI provides a graphical interface with support for mouse input.
  3. Security: UEFI provides more advanced security features, such as Secure Boot, which helps to prevent the loading of unauthorized operating systems or drivers.
  4. Legacy Support: BIOS has support for legacy hardware and operating systems, while UEFI has limited support for legacy hardware and operating systems.
  5. Driver Support: UEFI provides more advanced driver support, including the ability to load drivers directly from the firmware interface.

Overall, UEFI is a more advanced and versatile firmware interface than BIOS, providing more modern hardware support, a graphical user interface, and advanced security features.