In 1959, Newmark introduced what became known as the Newmark-beta method of numerical integration used to solve differential equations. The method is still widely used in numerical evaluation of the dynamic response of structures and solids, such as in Finite element analysis. He later helped to develop the first digital computers, the ILLIAC II, which was one of the first transistorized computers. It was also designed to use transistors that were not even invented yet. The ILLIAC-II eventually led to the development of computer software for engineering.