Click the Data tab and select Data Validation in the Data Tools group. A Data Validation dialog box will appear. Under Allow, click the drop-down arrow and select List from the drop-down list.

Excel’s data validation feature offers an efficient way to perform a variety of tasks. This collection of techniques demonstrates several handy ways to put data validation to work.

Excel's data validation feature is more versatile than you might think. Learn how to use literal values, input values, list values, and even formulas to restrict input date values using data ...

The "Data Validation" dialog box opens. Use the "Settings" tab options in the dialog box to limit the type of data that can be entered.