The Harvard Mark II was an early electromechanical computer developed at Harvard University in the 1940s. It was designed by Howard Aiken and built by IBM. The machine was an improvement over its predecessor, the Harvard Mark I, and was used primarily for scientific calculations. Completed in 1947, the Harvard Mark II utilized a combination of mechanical and electrical components to perform calculations. It was capable of executing complex mathematical operations and played a significant role in the development of computing technology, paving the way for future advancements in the field.