A typical year has 365 days. However, every four years, we have a leap year which adds an extra day, making it 366 days. This extra day is added to the month of February, which then has 29 days instead of the usual 28.
The reason for this adjustment is to keep our calendar in alignment with the Earth’s revolutions around the Sun. It takes approximately 365.25 days for the Earth to complete one orbit around the Sun. By adding an extra day every four years, we account for the additional 0.25 days each year, ensuring that our calendar remains accurate over time.