Question: what is the difference between on time and in time?
Answer: In time means arriving a bit earlier then required time. For instance, I was supposed to attend a lesson at 10:00 AM, but I arrived at 9:56 AM. On time means arriving exactly hour or a bit late. For example, I was supposed to attend a lesson at 10:00 AM but I arrived at 10:00 AM or 10:05 AM.