An engineering degree will be awarded to you after 4 years of study in a specialized branch like Computer science, Mechanical, Electrical, Civil and so on. Engineering degrees in India are generally B.E or B.Tech. The degree is the next step after class 12 for interested and eligible students. The engineering diploma is the course of three years done after class 10. For e.g technicians in most manufacturing as well as production units and such are diploma holders .They can obtain a degree in engineering through lateral entry which means that they join the 2nd year of engineering. An engineering certificate is just a short term course and is mostly offered in specializations. Hope this clears your doubts.