This refers to the conversion efficiency of the power supply.

Convert from alternating current to direct current. There is a concept of PFC. If the PFC is active, the conversion efficiency will be high and power will be saved. If it is passive, it will be very low. When choosing, try to choose active ones

Better power supplies will be selected under the 80PLUS trademark. Refers to efficiency above 80%.

Bronze, Silver, and Gold medals are more than 80% stronger power.