👉 In mathematics, a signal is an object that can be described by a mathematical function. Signals are often used in physics and engineering to model physical phenomena such as sound or light propagation. A signal's amplitude (or power) represents its strength or intensity; its frequency represents how rapidly it changes over time. A signal's phase, on the other hand, describes the direction of the signal's change relative to a reference point. Signals can be classified into two main categories: linear and non-linear signals.
