Shadow Clone Jutsu
Similar to the Clone technique, this technique creates clones of the user. However, these clones are actual copies, not illusions. The user's chakra is evenly distributed among every clone, giving each clone an equal fraction of the user's overall power. The clones are capable of performing techniques on their own and can even bleed, but will usually disperse after one or two solid blows, though even then it may not be enough. The clones can also disperse on their own. The clones will be created in roughly the same condition as the original. Shadow clones can't be distinguished from the actual person even by the Byakugan because the clones have the exact same amount of chakra and aren't made from any other substance.
Substitution Jutsu
With this technique, users replace their own body with some other object, generally with a block of wood, the moment an attack lands. This creates an optical illusion, making the enemy think the attack was successful. From this, the user can use the lapse in the enemy's attention to attack or flee from the battlefield. Explosive tags can be attached to the replacement for an added surprise. It's a basic ninjutsu even taught at the academy, but it's a useful art that can be applied in variety of situations.
Transformation Jutsu
Given all the missions ninja are assigned to - battle, intelligence gathering, diversions - this is a priceless ninjutsu. It is typically used to change into people other than oneself, but one also has the ability to change into animals, plants, and even inanimate objects like weapons. This gives this technique an abundance of uses. The transformation of a skilled shinobi will be exactly like the genuine article, so it will be impossible to tell the two apart. On the other hand, a transformation performed by an inexperienced person will have obvious discrepancies. It will be impossible to deceive anyone with it. This is one of the most basic ninjutsu, as such most shinobi know how to perform it.
Surface Climbing Technique
During missions and other situations, a shinobi often has to scale different surfaces, as well as run over uneven terrains. The surface climbing technique is applied to allow the shinobi to walk up surfaces by using chakra to stick to them. This same technique this can also be used to walk over the surface of water by distributing their weight around the water surrounding their feet. A more difficult technique to master from its original, but usually done so as a genin.