It simply prevents users from modifying locked cells within the worksheet.

Protection and security in Microsoft Excel involve measures to control access and safeguard the workbooks:

1. Password Protection: Secure workbooks and sheets with passwords.
2. File-Level Security: Use OS permissions to control file access.
3. Sheet and Cell Protection: Limit editing and viewing rights.
4. Digital Signatures: Verify file integrity with digital signatures.
5. Trusted Locations: Designate safe locations for files.
6. Macro Security: Control macro execution for safety.
7. Encryption: Password-protect and encrypt Excel files.
8. Collaboration: Share workbooks securely with permissions.
9. Audit Changes: Track and review workbook modifications.
10. Information Rights Management (IRM): Define policies for data protection.