The full form of USB PD is USB Power Delivery. It’s used on Technology ,General in Worldwide

USB Power Delivery (USB PD) or Universal Serial Bus Power Delivery (USB PD), is a fast charging standard that delivers higher levels of power than standard charging. USB PD enables flexible power delivery up to 100W along with data over a single cable.

USB Power Delivery is a separate specification that can work across USB 2.0 and 3.0 ports and cables, but you’ll still need a USB Type-C port too due to the communication pins used by the standard.

It is up to device manufacturers to support USB Power Delivery in addition to the mandatory charging modes of the basic connection type. That means that both the device and charger have to be compatible with the specification to maximize charging speeds, just like with Quick Charge, Pump Express, and other standards.