The Anno Computatri calendar uses 1970 CE as its Year 0 because this date serves as the foundation of how virtually all modern computing devices track time. When a computer, smartphone, or any digital device needs to know “what time is it?”, it calculates this by counting the number of seconds that have elapsed since midnight UTC on January 1, 1970.
This standardized starting point is known as the “Unix epoch” or “Unix time,” and it was established during the early development of the Unix operating system in the late 1960s and early 1970s. When the creators of Unix needed a consistent way to track time across computer systems, they chose January 1, 1970, as a practical, round-number starting point that was close to the present day at that time.
The concept is elegantly simple: rather than dealing with complex calendar calculations involving months of different lengths, leap years, and historical calendar adjustments, computers simply count seconds from a fixed reference point. This approach makes time calculations more efficient and eliminates many sources of error.
Today, this epoch-based timekeeping system underpins nearly all modern technology. When you schedule a meeting on your calendar app, check the timestamp on a message, or set an alarm on your device, the underlying system is converting between human-readable dates and the total seconds since the epoch.
The Anno Computatri calendar makes this hidden timekeeping system visible and accessible, allowing humans to conceptualize time the same way our digital devices do. By adopting AC, you’re not learning a new arbitrary system—you’re aligning with the temporal framework that already powers our digital world