How to know if my computer boots using UEFI in Ubuntu

So, I'm just wondering which technology my computer booting with whether it's BIOS or UEFI. Here is the tool that I found useful to help me achieve that goal: efibootmgr.

1. Install efibootmgr:

$ sudo apt-get install efibootmgr

2. Check if my computer's using UEFI to boot:

$ sudo efibootmgr

if the result is as following:

EFI variables are not supported on this system.

the answer is NO.


For more information about UEFI, please read this article: https://www.happyassassin.net/2014/01/25/uefi-boot-how-does-that-actually-work-then/