Learn these top skills to create your own formulas and functions. : Overview of formulas in Excel : VLOOKUP : SUM function : COUNTIF function : IF function : IFS : SUMIF : SUMIFS : Automatically number rows : Calculate the difference between two dates : Define and use names in formulas : Combine text from two or more cells into one cell More ways to learn : Ask an expert in the Excel Tech Community : Get support in the Answers community