For 500 years after the Buddha died, people worshiped the symbols we have been looking at. Then, for some reason that is not certain, people started making Buddha statues. The earlier symbols weren't replaced by the statues; in fact many of them were included.
Let's look at some statues and see what has remained of the old symbols and what new ones we can find.

A Halo
is an image of light, usually
associated with the head.

In relation to holy and enlightened beings the light of a halo symbolises truth, wisdom and purity of heart. This light dispels the darkness (of ignorance). Notice the halo and flaming torch on the Statue of Liberty.
Light is not a solid 'thing' so it has to be symbolised. Because the sun is our most important source of light a round disk behind, or surrounding, the head is the most common form for a halo. A halo at other parts of the body is called an aura. In the pictures on page five and eleven, the halo is quite plain. Light radiating from the body is sometimes related to the energy centres explained in yoga. On pages 6,7,13 and 29, a head 'flame' can be seen. This has a similar meaning to the halo - energy radiating out from the top chakra.