How do I use data validation in Excel?

To use data validation in Excel, you need to follow these steps:

1. Select the cells you want to apply data validation to
2. Click on the 'Data' tab in the ribbon at the top of the screen
3. Click on the 'Data Validation' button
4. In the 'Data Validation' window, select the type of validation you want to use
5. Enter the criteria for the validation
6. Click 'OK'

Data validation is a useful tool in Excel because it allows you to control the data that is entered into your spreadsheets. For example, you can use data validation to ensure that only certain types of data are entered into a cell, such as dates or numbers. This can help prevent errors and inconsistencies in your data.