Traditional computer-aided tutoring systems provide an educational material that includes static pages for students, but they do not consider the differences among students. So computer-aided education systems might not be alternative for traditional education in the classroom as well as obtain acceptable profit in point of the instructional quality in education. In this paper, Adaptive Educational Hypermedia System (AEHS) has been observed because of having different architecture and design approach, and making superior the instructional efficiency on the computer aided tutoring systems. General architecture of AEHS is also presented. Building up the student model that is a central component of the AEHS, and determining the knowledge level of user about the domain are explained with an application. Moreover the superiorities of AEHS according to computer-aided tutoring systems are presented and the existing studies about the AEHS are evaluated.