Facebook is the number 1 social media community. It is then no wonder that Facebook gets targeted by malicious or spamming identities.
If you get spammed by messages it is most of the time your own fault, you applied to an application on Facebook and gave them the permission to use and spam your Facebook profile. If you get targeted by malicious identities you need to know how to spot them and how to keep yourself safe.
These things you can do to keep your Facebook profile spam free.
Change your password
Changing your password is a good way to stop spam on your profile. Once you change your password the applications (robots) that spam your profile need to re-authenticate to your profile.
Enable Facebook HTTPS instead of HTTP
Go to "Account" -> "Account Settings" .Under "Account Security", hit the change button and check the box that says "Browse Facebook on a secure connection (https) whenever possible"
Remove unwanted application
Remove all the references to the application ie news feeds and wall post and remove the application from the installed facebook applications
Account->Privacy Settings->Applications and Websites
If you have unwanted devices go to: account -> security settings, and check whether anything needs to be modified there. For example, ensure logon notifications are active, permission is needed for unrecognized devices, and remove any trusted devices which don't belong to you.