This image illustrates the basic differences between the three Saturn launch vehicles developed by the Marshall Space Flight Center. The Saturn I, consisted of two stages, the S-I (eight H-1 engines) and the S-IV (six RL-10 engines). The Saturn IB (center) also consisted of two stages, the S-IB (eight H-1 engines) and the S-IVB (one J-2 engine). The Saturn V consisted of three stages, the S-IC (five F-1 engines), the S-II (five J-2 engines), and the S-IVB (one J-2 engine).