Extensible Firmware Interface (EFI), like legacy BIOS, initializes hardware components and operating system image files when a computer starts. EFI supports more modern features and customization options than BIOS, enabling faster boot times.
It stores all the information about initialization and startup in a file with a
.efi extension, which is stored on a special partition called EFI System Partition (ESP). The ESP also contains the boot loader programs for the operating system that is installed on the computer.