ELI5: Explain Like I'm 5

signal processing

Signal processing is a way of changing or manipulating how a sound is heard. For example, if you are listening to a song on the radio, a signal processor takes the sound of the music and changes it so that it comes out of your speakers louder and clearer. It can also add special effects like reverb or echo, so that the music sounds even better. Signal processing is used in all kinds of audio equipment, from radios to music players.