Chakra is an energy that exists in all life forms, molded together from our physical energy, through our body cells, exercise and our spiritual energy through meditation, knowledge, experience. They flow within us in a circulatory system, much like blood flowing in veins, it is the very source of energy that ninjas practice through training to make it grow stronger. With it, ninjas can perform the techniques, the basic ones divided in 3 categories; ninjutsu, genjutsu, taijutsu. Using different combinations of handseals, allows one to control and perform an vary of jutsus. However, chakra is considered a life force to a ninja, completely depleting one's energy can cause exhaustion, fatigue or worst cases, death.
The 5 elements consist of Fire, Water, Earth, Lightning and Wind, each possessing different relationship with each other in strengthens and weaknesses. They are a direct result of altering chakra through nature manipulation, taking on an elemental properties and characteristics to perform techniques. Each person has a natural affinity towards one of the elements, and these affinities can be inherited through genetics as clans like Uchiha that possess an affinity to fire. Learning and mastering nature transformation usually takes any years even for an affiliated element, however a person is not limited to a single element but its increasingly difficult to learn others. In some cases, ninjas possessing a inherited bloodline can combine 2 basic elements together to create a new one.