Modern electronic systems are increasingly digital: digital microprocessors,
digital logic, digital interfaces. Digital logic is easier to design and understand,
and it is much more ﬂexible than the equivalent analog circuitry would be.
As an example, imagine trying to implement any kind of sophisticated micro-
processor with analog parts. Digital electronics lets the PC on your desk
execute different programs at different times, perform complex calculations,
and communicate via the World Wide Web....