"Chakra is a latent energy field that suffuses the Human Path. It is not uniform, but rather has distinct subcomponents, believed by scholars to be created by the Sage for use by his various companions. Human chakra, which is the predominant type of chakra on this Path, is one component." He poured a vial of liquid colored a faint yellow into the clear beaker, leaving it still transparent.
"Nature chakra is simply another component," he said, holding up a vial with a darker red fluid. "It is the predominant type of chakra present on the Seventh Path." He poured in a few drops, turning the solution faintly pink.
"Ambient chakra is a mixture of numerous subtypes of chakra, which, apart from human chakra for humans and nature chakra for summons, are currently impossible to interact with, survey, and study. All humans possess an affinity for human chakra, though only ninja are capable of using it effectively."