What is the four letter acronym for firmware which essentially is responsible for "starting up your computer"? The firmware provides runtime services or operating systems, performs hardware initialization, and then loads a bootloader. The term first appeared and appeared in 1975 to describe a system implemented later in 1981 by IBM PCs. Today, this technology is in transition towards a process referred to as "UEFI" - Unified Extensible Firmware Interface.
Answer to yesterday's question: "Kernel" is the program. A full kernel controls all hardware resources via device drivers, arbitrates conflicts. It is one of the first programs loaded on startup. Critical kernel code is generally loaded into a separate area of memory and that part is protected from access by application software. There are different kernel architectures - there can be monolithic kernels, microkernels - Linux kernel is a Unix-like kernel which is both monolithic and modular, as loadable kernel modules can be inserted or removed at runtime.