For USB Power delivery.
The USB Power brick has a chip in it that the laptop queries to find out what levels of power it can deliver.
The USB cable has a chip in it that the laptop queries to find out what level of power it can safely deliver without damaging the cable.
The laptop then decides what to ask for.
So, when the power brick is a 180W brick, and the cable is a 240W cable, the laptop will ask for up to 180W.
When the power brick is 240W, and the cable is 100W, the laptop will ask for up to 100W.
But a word of warning, some cables and power bricks lie about what they are capable of and it ends is bad smoke.