Howard Joel Wolowitz is a fictional character and one of the protagonists on the 2007–2019 CBS television series The Big Bang Theory, portrayed by actor Simon Helberg. Among the four main male characters in the show, Howard is distinctive for being an engineer—rather than a physicist—and lacking a PhD. He is named after and based on a computer programmer known by the show's co-creator; Bill Prady. Howard is the only starring character who has been to the International Space Station. Along with Sheldon Cooper, Leonard Hofstadter, and Raj Koothrappali, Howard is part of the central cast of the show.