We mark time with the events of our lives, with the holidays and the family celebrations that we use on an annual basis or on a regular basis. This sort of helps us to keep track of the progression of our lives, of the progression of our lives. For example, we will remember the last Christmas dinner that a loved one was present at. We think of those things. Well, what year was that? Well, that was the last year that Grandma was at Christmas. We also use things to remember whether someone was born, not just on the other end of life, but at the beginning of life.