Periodic events are occurrences that happen at regular intervals, such as daily, weekly, monthly, or yearly. Examples include seasons, which change every few months, and birthdays, celebrated once a year. These events can be natural, like the phases of the moon, or human-made, like holidays. Understanding periodic events helps in planning and organizing activities. For instance, knowing that daylight saving time occurs twice a year allows people to adjust their schedules accordingly. Additionally, periodic events can be observed in science, such as the tides, which rise and fall in a predictable pattern due to the gravitational pull of the moon.