Definition:
Computers store the date as a number representing the number of full days since midnight January 1, 1900 plus the number of hours, minutes, and seconds for the current day.
Excel's date and time functions, such as =NOW and =TODAY use this number for calculations involving dates or to add the current date and/or time to a spreadsheet.
On Macintosh computers, the serial date begins in January 1904.
Also Known As: Serial Date, Serial Number
