Is there any difference between broadband and datacard internet?

Yes, broadband is a type of service that gets you to the internet. It is generally faster then the other alternatives. And it allows phone calls to be made and received while connected to the internet. Other types of internet service are DSL and dial-up.
technology seems to have multiple names for the same thing. broadband is internet its just more common to describe the different types of broadband ex. "mobile broadband"