1. 1 Introduction o Classification of signals 1. Analog signal-A continuous-time signal with a continuous amplitude 2. Digital signal-a discrete-time signal with discrete-valued amplitudes represented by a finite number of digits1.1 Introduction ⚫ Classification of signals 1. Analog signal—A continuous-time signal with a continuous amplitude. 2. Digital signal—A discrete-time signal with discrete-valued amplitudes represented by a finite number of digits