Artificial Intelligence is the key technology in new applications, ranging from banking systems that detect attempted credit card fraud, to telephone systems that understand speech, to software systems that notice when you're having problems and offer appropriate advice. These technologies would not exist today without the sustained federal support of fundamental artificial intelligence research. At present, knowledge-based system technology requires the means to provide efficient and robust knowledge bases, while database system technology lacks knowledge representation and reasoning capabilities. The time has come to face the complex research problems that must be solved before we can design and implement real, large scale software systems that depend on knowledge-based processing. The essential of technology use operational level for knowledge-based system applications. In this article the author discussed artificial intelligence and knowledge based systems technologies and their applications.