"While it may seem that PC hardware beeps when it is powered on
as a matter of course, in fact, there's a bit of code that makes
that beep happen. That piece of code is the boot firmware. On most
PCs, it's called the BIOS. (The word is an acronym for basic
input/output system.) The BIOS provides the underlying hardware
support that early x86 operating systems used to access disks,
monitors, and just about everything else..."