Protecting your sensitive data is crucial, especially when using software like Microsoft Excel. Adding a password to your Excel files can greatly enhance security and prevent unauthorized access to your information. Here's a simple guide on how to add a password to Excel:

1. Open your Excel file that you want to password protect.
2. Click on 'File' in the top left corner of the Excel window.
3. Select 'Info' from the menu on the left.
4. Click on 'Protect Workbook' and then choose 'Encrypt with Password'.
5. Enter your desired password and click 'OK'.
6. Re-enter the password to confirm and click 'OK' again.
7. Save your file to apply the password protection.

By following these simple steps, you can add a password to your Excel file and keep your data safe from prying eyes. Remember to use a strong and unique password to maximize security.