whatis uefi
UEFI
Also known as: BIOS, EFI, ESP, EFI System Partition
Modern PC firmware that replaced legacy BIOS, booting from .efi files on a FAT-formatted EFI System Partition (ESP).
What Is UEFI in Linux?
UEFI reads bootloaders directly from the EFI System Partition, typically mounted at /boot/efi or /efi. Boot entries are stored in NVRAM and managed with efibootmgr. It requires or strongly prefers GPT partition tables.
Legacy BIOS instead ran code from the first sector of the disk. UEFI also enables Secure Boot, which verifies each stage is signed before running it.
Example
ls /sys/firmware/efi && echo "UEFI"
efibootmgr -vLearn more about UEFI
- BIOS vs UEFI: What's the Difference? BIOS and UEFI are the firmware interfaces that initialize hardware before the OS loads. Understanding the difference matters for installing Linux, setting up dual boot, and configuring Secure Boot. This guide explains both clearly.
- Secure Boot Explained: What It Is and How Linux Handles It Secure Boot is a UEFI feature that verifies the digital signature of the bootloader before running it. Most major Linux distributions handle it transparently, but some setups require additional configuration. This guide explains how it works and what to do.
- How to Dual Boot Linux and Windows Dual booting lets you run Linux and Windows on the same machine, choosing which to start at boot. This guide covers the right order to install them, how to resize Windows partitions, how GRUB handles the boot menu, and common problems to avoid.