I have a half dozen codes that a user can enter into a field. Once a code is entered into a cell (e.g. 'KM-1'), I'd like the user to be able to hover the mouse over the cell and he'd see the description of the code (e.g., 'Develop/Launch Comms Campaign'). I don't want to populate the cell with the code & full description as a default. Is there a way to set that up in Excel 2010?