Dr. A.P.J. Abdul Kalam, known as the Missile Man of India, played a pivotal role in developing India's missile programs including IGMDP (Integrated Guided Missile Development Program) which produced missiles like Prithvi, Agni, Akash, Trishul and Nag. He served as DRDO chief and later became President of India. Dr. U.R. Rao was a space scientist, Dr. Chidambaram is a nuclear physicist, and Dr. Homi Bhabha was the father of India's nuclear program.