arm waving???

yesterday i saw my bearded dragon waving his arm, anyone no why?

They do it to communicate....perfectly normal. Mine did it alot when they were young, but kinda outgrew it.

They would always wave when I walked in the room....

....and the freak that I am would always wave back.

Here is a read on arm waving:
http://www.beardeddragon.org/articles/armWaving/