Microsoft Excel: Restricting Cell Input Data
Some of the Excel worksheets you create will be shared by other people... perhaps even used to gather responses from them. You can specify certain cells where others will enter the data you are seeking. And you can set up your answer cells so that the data others might enter will be exactly the kind you need and in the format you want. Controlling entries in this way is referred to as “data validation” which means you can set up Excel to reject any data that someone might try to enter in a form you don’t want.