Associating midnight with 00 : 00 .
The start of day is one option that has the benefit of aligning with many religious calendars which singularly define a start of day , such as the Hebrew calendar and the Islamic calendar .
Associating midnight with 00 : 00 and the start of day is one option that has the benefit of aligning with many religious calendars which singularly define a start of day , such as the Hebrew calendar and the Islamic calendar .