This bit from a Bitwig Grid tutorial shows how the Min/Max module can split any signal into its positive and negative polarity halves by comparing the input against an implicit zero reference when only one input is connected.
The positive portion comes out of the maximum output, the negative out of the minimum, giving you two separate streams to process independently. This is the same principle behind why guitar cabinets sound the way they do: the positive and negative sides of a signal are physically affected at different rates, producing asymmetry that reads as warmth.
From there, the walkthrough patches each half into its own distortion stage, so the negative portion gets a different character than the positive. That difference in treatment between the two halves is what creates the distinctive tonal quality associated with analog-style asymmetrical clipping.