The 24-hour clock, also known as military time, is a timekeeping system that divides the day into 24 hours. It starts at midnight, represented as 00:00, and runs until 23:59. This format eliminates confusion between AM and PM, making it easier to schedule events, especially in professional and military contexts. In the 24-hour clock, hours are counted from 0 to 23. For example, 1:00 PM is written as 13:00, and 11:00 PM is written as 23:00. This system is widely used in many countries and is standard in transportation timetables, such as airlines and trains, to ensure clarity.