An object is a material thing that can be seen and touched.
- An object is intuitively assumed to exist and to be responsible for a unified experience, consisting of visual and other sensations and perceptions.
- Every object, material, medium or substance is made of matter of one kind or another.
- The key differentiating factor between objects is the atoms, molecules and compounds they are constructed from.
- Atoms, molecules, elements and compounds react to light in different ways because of their atomic structure and the way they are mixed together.
- In the case of opaque objects, it is the form their surface takes that determines what happens when they are exposed to light.
- Translucent and transparent objects behave differently because light can travel through them.
- Surface finish affects the appearance of objects. A smooth and polished surface behaves differently from one that is rough, textured or covered in ripples.