A formula is an expression telling the computer what mathematical operation to perform upon a specific value. When referring to computer software, formulas are used in spreadsheet programs, such as Microsoft Excel. Using formulas in spreadsheets can allow you to quickly make calculations and get totals of multiple cells, rows, or columns in a spreadsheet.
In the picture below is an example of a Microsoft Excel formula =SUM(A$1:A$3), which adds the total of cells A1, A2, and A3. In this formula, SUM is the function of the formula.
Press the keyboard shortcut key Shift+F3 to open the Excel Formula or Insert Function window.
A formula is not be seen unless the cell is selected. If you want Excel or Google Sheets to always show you formulas instead of the values use the shortcut Ctrl+`.
Absolute cell reference, Autosum, Formula bar, Lookup, Range, Relative cell reference, Spreadsheet terms, SUM, SUMIF, Whatif