What does the mysql/php error -Incorrect table name "- mean?

I have a registration system. But, when you try to register, and submit it says Incorrect table name``. What is the problem?

What does the mysql/php error -Incorrect table name "- mean?
It means that the table name you're trying to use - a blank string - is invalid. If the name of the table is a variable, the variable has no value.
Reply:the table name is incorrect?