Years

Years are a unit of time used in the Gregorian calendar to measure the duration between two events. A year is approximately the time it takes for the Earth to complete one orbit around the sun. The Gregorian calendar, which is the most widely used calendar system today, defines a year as 365 days, with an additional day added every four years to account for the extra time it takes for the Earth to orbit the sun (leap year).

Key Concepts

Leap Year: A year that is evenly divisible by 4, except for end-of-century years, which must be evenly divisible by 400 to be a leap year.
Common Year: A year that is not a leap year, having 365 days.
Julian Year: A year of 365.25 days used in the Julian calendar.
Tropical Year: The time it takes for the Earth to complete one orbit around the sun, approximately 365.24219 days.

Study Tips

When studying years, it's important to understand the concept of leap years and how they affect the calendar. Practice identifying leap years and calculating the number of days in different years to reinforce your understanding. Additionally, familiarize yourself with other calendar systems such as the Julian calendar and the concept of the tropical year.