What is a DAC (Digital-to-Analog Converter) and How Does it Work?

What is a DAC, and why would you need one?

6 Ways To Connect An Audio Mixer To A Computer (Mac Or PC)

Fosi Audio Q4 Desktop DAC Headphone Amp for PC Mini Stereo Headphone Amplifier Combo USB Optical Coaxial to RCA AUX Digital-to-Analog Audio Converter Adapter for Home Powered Speakers