Compression is an effect that subtly shapes the dynamics of your playing, often unnoticed by many but greatly appreciated by experienced musicians for its ability to enhance and refine the sound. It can smooth out the tone of a brittle-sounding Telecaster, accentuate the punch of a bass, and bring clarity and presence to the attack of a pick on strings. In more extreme settings, it can significantly squash the signal, contributing to the distinctive 'cluck' and 'pop' of a Stratocaster in a country music setting or the nuanced playing of artists like Mark Knopfler.