When a password is attached to a drawing, the password encrypts the drawing and prevents unauthorized people from viewing it.
Password-based encryption helps secure drawing data when you collaborate on projects. Specifically, when you maintain a password for a drawing, you can help prevent unauthorized viewing of the drawing when it is sent to others.
If you add a password to a drawing and save the drawing, the drawing is encrypted and cannot be reopened until the password is entered.
To view the data in a password-protected drawing, you must first obtain and enter the password. After you enter the password, it stays with the drawing, even if you modify and save the drawing, unless you remove the password.