As explained in the Critique of Pure Reason A 320/B 377
Perception: A representation with
Sensation: A perception that relates
only to the knowing subject as a modification of its own state (e.g.,
pain) and without reference to any other object.
Cognition: Objective perception.
Intuition: Cognition relating
immediately to an object, which is single.
Empirical Intuition: Wholly contingent
sense perception of a single object.
Pure Intuition: Object necessarily
joined to all empirical intuitions in advance of any particular
perceptions. There are two pure intuitions: space and time.
Concept: A cognition relating
mediately to an object by means of some feature that several things have
Empirical Concept: A concept of what
several objects of sense perception have in common.
Pure Concept: A concept of what
objects must have in common.
Notion: A pure concept having its
origins in the understanding alone.
Idea: A concept of reason (not
understanding), transcending the possibility of all experience. As with
other concepts, these may be pure or empirical.