The USB I/O Bit features 44.1K/12-bit audio conversion for high quality sound. It is also "DC coupled," which means that in addition to sending and receiving signals like music, it can also send and receive control voltages.
Sending and receiving control voltages allows you to use software programs like Max, PD, and CV Toolkit with the USB I/O Bit to control other Bits by creating "virtual" Bits like sequencers, low-frequency oscillators, and more. You can also control the aforementioned programs with Bits to create hardware controls for your software.
The USB I/O Bit will appear to your computer as an audio interface and its input and output routing can be selected as with any other audio interface. The Bit can only be selected as either an input or output device at a given time but multiple USB I/O Bits can be used at once.