A month is one of the twelve divisions of a year. Each month has its own name (January, February, March, and so on) and lasts between 28 and 31 days. When someone asks “What month is your birthday?” they want to know which of these twelve periods contains the day you were born.

Most months last around 30 days. February is the shortest month with 28 days (or 29 in a leap year), while seven months have 31 days.

We use months to organize our lives in manageable chunks. Your school year divides into months, subscriptions often charge by the month, and when planning ahead, people think in terms of months: “We're moving in three months” or “The science fair is next month.” A monthly event happens once per month, like a club meeting or a magazine. When you say something takes “a month,” you mean roughly four weeks, though the exact number of days varies depending on which month you're talking about.