Copy Paste Vs Duplicate

Hey guys,

Can someone please explain the different usage for copy and paste vs duplicate? in PS duplicate used to clone the item but zero out the values, now it seems to do something different. and if i want to clone sub items or takeoff items with zero value its copy/ paste. I can adapt but i just need to know the different purposes (Personally the copy paste is slower, and it doesn't open the property box, so its 3-4 clicks before i can edit values, it adds up)

Cheers