Show Formulas in Excel Spreadsheets

When using formulas (and functions) in Excel, the result is displayed in the cell, as opposed to the details of the formula/function.
You can change this by pressing Control + Grave (`).
The Grave key is next to the number 1 on the top left on most keyboards, but may be different on some keyboards.
Press Control + Grave (`) again to switch back to displaying the results.