Anti-spam Settings

What is spam?
How to deal with spams?
What is blacklist,and how to configure?
What is whitelist,and how to configure?
How to keep from spams?
If I receive a spam and the sender is me,what's the matter?
How to know where the real send from?
Why is my account blocked?
When an email in the Spam folder is not a spam, how should I do?