If you have an appointment at 10:00 and you came at 10:00, you are on time. If you came before 10:00, you are in time.

Hello Nuria, I don't think you'll get in any trouble if you switch between the expressions, but in my experience, "on time" is used when you are talking about something that is scheduled to happen at a specific time, ("the package was delivered on time") and that's the end of it, while "in time" usually means something happened so that it was ready for something to else happen, ("thankfully, I arrived in time to catch my flight at the airport"). Sulaiman's example is good, if you arrive before 10:00 you have arrived "in time" to make your meeting (you are ready for your meeting). Hope that helps, I'm new here :)

due 10:00 "on time" = 10:00 "in time" = 9:45 -- 10:15

A small correction to your heading, it reads... Can someone explain me the difference between, it should read.... Can someone explain TO me the difference between

In my vocabulary. 'on time' "Your appointment is for 9am, be there on time please" 'in time' "my appointment was for 9am, I made it there just in time"