Using the same date formats in two different cells means you can use functions for specific date-based calculations.

It's easy to change the date format in Microsoft Excel. You just need to use the "Date" drop-down menu, which gives you plenty of options.

This chapter summarizes the time intervals, date and datetime informats, date and datetime formats, and date and datetime functions available in the SAS system. The use of these features is explained ...

DATEDIF(), which means Date + Dif, is a compatibility function left over from Lotus 1-2-3 that Microsoft adopted in Excel version 2000. It's fallen off current Excel menus, but you can still use ...

Informats and Formats The SAS System converts date, time and datetime values back and forth between calendar dates and clock times with SAS language elements called formats and informats.