Type C cables that Charge Rapidly.

Hi I got a 6P a while back I'm useing my Nexus 6 charger/adaptor an I notice that when I plug a white cheap USB to type c cable to my phone it says Rapidly charging..So I ordered 2 Spigen USB 3.0 to type C cables an when I plug them into my Nexus 6 adaptor it says just Charging but seems to charge fast..I also ordered a Cheotech Faster charger that came with a USB to type C cord an when I plug it in it says just Charging if I use that cheap White type C cable with the Cheotech charger it says Rapidly Charging..Very weird..So I'm wondering even tho it says just charging is it still Rapie charging fast.My wife hooks up here S7 edge to the Cheotech an it says Rapidly Charging..