Into
Part of speech: preposition
Definition: Going inside (of) Going to a geographic region. Against, especially with force or violence. Producing, becoming Intensely interested in or attracted to. Taking distinct arguments to distinct values. The operation of division, with the denominator expressed first. Investigation of a subject.
Onto
Part of speech: preposition
Definition: upon, on top ofaware ofbeing an onto function with a codomain of (see below)
Part of speech: adjective
Definition: assuming each of the values in its codomain; having its range equal to its codomain