Analog versus digital
The first thing to remember is that we live in an analog world. Nothing is instantaneous and everything is continuous. This is the reason why we can't teleport, sadly!
Similarly, analog signals are continuous and everchanging; they don't jump instantaneously but instead smoothly transition from one state to another. A prime example of an analog signal is the old Amplitude Modulation (AM) radio. You can see in the following figure how the smooth data signal is modulated onto a smooth carrier wave to create the smooth AM signal. Here, the pitch is represented by how quickly the amplitude is changing and the volume is represented by how great the amplitude is:
Figure 2.1 – Analog signal example
In contrast, a digital signal is one that is sampled at known points in time. When the signal is sampled, it is checked to see whether it is above or below a certain threshold, which will determine whether it is a logic 0 or...
