The shortest month of the year is February. It has 28 days in a common year and 29 days in a leap year, which occurs every four years. The distinction is notable because February is the only month that does not have at least 30 days. This characteristic makes February unique and is often a point of reference when discussing calendars and time. Historically, the length of February was altered by the Romans, leading to its current status. Many cultures and traditions celebrate various occasions, such as Valentine's Day, during this abbreviated month.