Some recent threads inspired me to want to make a list of the different notions of time we need in physics (As I write this, I am focussed on pecial and general relativity, but I've added some important notions that are used by other fields). Here's what I've come up with so far, I am interested if there are any additions or corrections.
Proper time. This is the sort of time measured by a clock. Proper time is an interval between two events, but in special and general relativity, this...