Step 1: Concept
Data security in spreadsheet software (like MS Excel or LibreOffice Calc) ensures that sensitive information is kept safe from unauthorized users.
Step 2: Meaning
Protecting a spreadsheet involves applying built-in encryption tools that require a user to enter a specific password to either open or modify the file.
Step 3: Analysis
• Open the desired spreadsheet document.
• Navigate to the File menu and click on Save As (or go to the Review tab and click Protect Sheet/Workbook).
• In the Save As dialog box, click on Tools and select General Options.
• Enter a strong password in the "Password to open" and/or "Password to modify" fields.
• Re-enter the exact password in the confirmation prompt and click OK, then save the document.
Step 4: Conclusion
Following these standard sequential steps ensures the spreadsheet file is securely locked.
Final Answer: 1. Go to File $>$ Save As. 2. Click Tools $>$ General Options. 3. Enter a password to open/modify. 4. Confirm the password and click Save.