Definition: The "Gregorian calendar" is a system for measuring time that is used by most of the world today. It was introduced by Pope Gregory XIII in 1582 to fix some mistakes in the earlier Julian calendar. The Gregorian calendar corrected the way leap years were calculated and adjusted the dates by removing 10 days. For example, when the change was made, what was October 5 became October 15.
The Gregorian calendar is an important tool for organizing our time and is widely accepted around the globe. It helps us keep track of days, months, and years accurately.