The boot process
The sequence of events that occurs between the time that you turn on a computer and
the time that it is ready for you to issue commands is referred to as the boot process or
"booting" your computer. The term "boot" comes from the word "bootstrap," which
describes a small loop on the back of a boot. Just as you can pull on a big boot using a
small bootstrap, your computer boots up by first loading a small program into memory,
then it uses that small program to load a large operating system. Your computer's
small bootstrap program is built into special ROM (read-only memory) circuitry
that's housed in the computer's system unit. When you turn on a computer, the ROM
circuitry receives power and it begins the boot process.
With a Windows computer, the boot process usually proceeds smoothly and, in a short
time, you can begin working with your application software. Sometimes, however, the
boot process encounters a problem that must be fixed before you can begin a computing
session. You can fix many of the problems that a computer might encounter during the
boot process—a valuable skill for keeping your own computer up and running. Make
sure, however, that you follow the guidelines provided by your school or employer if
you encounter equipment problems with computers in school labs or your workplace.
What is the purpose of the boot process? The boot process involves a lot of flashing
lights, whirring noises, and beeping as your computer performs a set of diagnostic tests
called the power-on self-test (POST). The good news is that these tests can warn you if
certain crucial components of your computer system are out of order. The bad news is
that these tests cannot warn you of impending failures. Also, problems identified
during the boot process usually must be fixed before you can start a computing session.
The boot process serves an additional purpose—loading the operating system from the
hard disk and into memory so that it can help the computer carry out basic operations.
Without the operating system, a computer's CPU is pretty much unable to communicate
with any input, output, or storage devices. It can't display information, accept commands,
store data, or run any application software. Therefore, loading the operating system is a
crucial step in the boot process.
Questions:
a. What is a boot process?
b. Name the two uses of a boot process.
c. What is the role to play for ROM in the boot process?
d. There are two types of boot process, warm boot and cold boot. Briefly describe
these two terms.
e. Briefly explain why in the right beginning the operating system (i) cannot be put
in the ROM, and (ii) cannot be found in the RAM.