Each rapid prototyping (RP) process has its special and unique advantages and disadvantages. The paper presents a state-of-the-art study of RP technologies and classifies broadly all the different types of rapid prototyping methods. Subsequently, the fundamental principles and technological limitations of different methods of RP are closely examined. A comparison of the present and ultimate performance of the rapid prototyping processes is made so as to highlight the possibility of future improvements for a new generation of RP systems.