The Five Aggregates are: Form (Rupa), Sensation/feelings (Vedana), Perception (Sanna), Mental Formation ((Sankhara) and Consciousness (vinnana).
Form (Rupa): The aggregate of form corresponds to what we would call material or physical factors. It includes our own bodies, and material objects as well. Specifically, the aggregate of form includes the five physical organs (eye, ear, nose, tongue, body), and the corresponding physical objects of the sense organs (sight, sound, smell, taste and tangible objects).
Sensation (Vedana): The aggregate of sensation or feeling we experience through contact is of three kinds - pleasant, unpleasant and indifferent (neither pleasant nor unpleasant). When an object is experienced, that experience takes on one of these emotional tones, the tone of pleasure, the tone of displeasure, or the tone of indifference.
Perception (sanna): The function of perception is to turn an indefinite experience into a definite, recognised and identified experience. It is the formulation of a conception of an idea about a particular object of experience.
Mental Formation (sankhara): The aggregate of mental formation may be described as a conditioned response to the object of experience. It is not just due to our past actions (the habitual energy stored up from countless former lives), but also the responses here and now motivated and directed in a particular way. All volitional actions,wholesome and unwholesome, are included in the aggregate of mental formations. The aggregate of mental formations is associated with karma, because intentional volitional acts create karma.In short, mental formation or volition has a moral dimension; perception has a conceptual dimension; feeling has an emotional dimension.
Consciousness (vinnana): Both the eye and the visible object are the physical elements, therefore they are not enough to produce experience by themselves. Only the co-presence of consciousness together with the eye and the visible object produces experience (eye consciousness). Similarly, ear, nose, tongue and body are the same. Consciousness is therefore an indispensable element in the product of experience. Consciousness is mere awareness, or sensitivity to an object.
There are: eye consciousness, ear consciousness, nose consciousness, tongue consciousness, body consciousness and mind consciousness. It is important to understand that this awareness or consciousness depends on the other aggregates and does not exist independently from them. It is an awareness but not a recognition, as recognition is a function of the third aggregate. This awareness is not sensation, which is the second aggregate.