This proejct serves the purpose of developing a software that can help designers of optical devices understand the properties of a waveguide, particularly the rib waveguide. This is done through an analysis method called the Effective Index Method which was proposed by Toulious and Knox in 1970. By using this method, the propagation constant of the waveguide can be calculated and hence the electric profile can be plotted. The software which I named EIM is written under the Windows environment which exhibits a good user interface ability. It is developed using Turbo C++ for Windows. The main focus of this project report will be on the theory of the Effective Index Method, the mathematics behind this method, the software development process, the resulats obtatined and of course, discussions on the possibilities of expanding this project.