Difference Between Basic Input/Output System (BIOS) and Unified Extensible Firmware Interface (UEFI)

This article covers an important concept in the field of the computer world. This article describes what is BIOS, what is UEFI, and differences between the BIOS and UEFI.

What is BIOS?

BIOS stands for Basic Input/Output System. It is a fundamental firmware interface that is found in computers. It is a tiny piece of code that is stored on a special chip called EPROM (Erasable Programmable Read-Only Memory). It contains the necessary instructions for the computer to start and load the operating system. The main objective of BIOS is to check the preferences that are stored in a CMOS chip to understand how the user wants the computer to operate.

What is UEFI?

UEFI stands for Unified Extensible Firmware Interface. It is a modern firmware interface that replaces the older BIOS in computers. Its main job is to keep important information about the device initialization which is stored on a special part of the disk. The primary reason for creating UEFI, is to tackle the limitations of BIOS and shorten the system boot time. It makes the computer start faster. It bridges the gap between the computer’s hardware and operating system, allowing for better compatibility, security, and functionality.

Difference between BIOS and UEFI

The differences between BIOS and UEFI are mentioned below.

Category	BIOS	UEFI
Release Date	1981	2002
User Interface	Basic UI navigation using the keyboard.	User-friendly graphical UI with mouse support.
Operating Mode	16-bit	32-bit/64-bit.
Partition Support	It supports upto 4 physical partitions, upto 2 TB.	It supports upto 128 physical partitions, upto 18 exabytes.
Security	It has basic security features, having no inherent security feature.	It supports secure boot, and prevents unauthorized OS.
Performance	It has slower boot times and limited hardware support.	It has faster boot times and is optimized for modern hardware.

Frequently Asked Questions on BIOS vs UEFI – FAQs

What does BIOS stand for?

BIOS stand for Basic Input/Output System.

Is the BIOS software or hardware?

BIOS is a software but, it’s stored on a hardware component on the motherboard.

Is BIOS the same for all computers?

No, BIOS is not the same for all computers.

Is BIOS on the motherboard or CPU?

BIOS is located on a chip on the motherboard, not the CPU.