Excel has over 475 formulas in its Functions Library, but we've selected the most popular, from date and time functions to mathematics and simple data manipulation.

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 ...

To highlight weekend dates, we’ll use the WEEKDAY () function in a conditional formatting rule. This function returns a number between 1 and 7 to identify the day of the week, as a date.