Comments to cells are a good way to document the purpose of the cell, or describe the formula etc.
To add a comment you can:
- Right-click the cell and select Insert Comment
- Press Shift+F2
- Choose Review-> Comments-> New Comment
You can control the display of the comments by going to Excel Options->Advanced button-> In the Display section select the Comment option you require. Or you can select Show/Hide Comments when the cell containing the comment is right-clicked.
Next – Formatting a Comment