At its core, an electrical signal is just a change in a property of electricity, like voltage or current. To send information from one place to another, we manipulate these properties in a specific pattern. Think of it like using a flashlight to send Morse code. A long flash could be a dash (a '1') and a short flash a dot (a '0'). By turning the light on and off in a sequence, you can send a message.

Electrical signals work the same way, but much faster and over wires. These wires, or cables, are the physical paths that guide the electricity from the sender to the receiver. The design of a cable is crucial because it needs to protect the signal from getting distorted along the way. Let's look at two common types.

You've probably seen a coaxial cable before. It's the thick, round cable often used to connect a TV to a cable box or a modem to the wall. Its name, 'coaxial,' comes from its structure: it has multiple layers that all share a single common axis, or center line.