曆法亦都係完整計時系統嘅一部份，有日期同時間就可以精確咁定義某個特定嘅時刻，現代嘅計時器可以顯示日期、時間同星期幾。
The calendar is also part of a complete system of timekeeping, with dates and times to precisely define a particular moment, and modern timers that display the date, time, and day of the week.