The convention of starting clocks at 12:00 rather than 1:00 is rooted in historical and cultural reasons. The 12-hour clock system, also known as the duodecimal system, has been used for centuries in various civilizations, including ancient Mesopotamia, Egypt, and Greece.
The choice to begin the clock at 12:00 instead of 1:00 likely stems from the division of the day into 24 hours. In this system, each hour represents a 1/24th portion of a day. Starting the clock at 12:00 allows for an equal distribution of the 24-hour cycle, with 12 hours dedicated to the first half of the day (from midnight to noon) and 12 hours dedicated to the second half (from noon to midnight).
Additionally, the use of 12 hours instead of 24 hours on analog clocks can be traced back to the ancient Egyptians and Babylonians, who utilized a base-12 number system due to its divisibility by several numbers. The number 12 has many divisors (1, 2, 3, 4, 6), making it mathematically convenient for measuring time, angles, and other quantities.
Over time, these conventions have become widely adopted and ingrained in various cultures around the world, leading to the common practice of starting clocks at 12:00.