Hand Seal

Hand Signs are used to create all forms of nin and genjutsu. There are different hand signs for every different techniques. While techniques may require a number of handsigns to work, a skilled ninja can use less or even one to preform the same technique. And example of this is the Water Release: Water Dragon Blast Technique, which needs a total of 44 handsigns to work. The Second Hokage however just needed to use one handsign to complete the technique, a testament to his skill.