ABSTRACT
We give a brief resume´ of STA as developed by Hestenes [1, 2, 3]. STA is the Clifford algebra of real four-dimensional space-time with a thoroughgoing geometric interpretation. It is built out of objects with direct geometric interpretations; the properties of these objects are specified by introducing algebraic operations that directly determine their interrelations. Furthermore, STA derives its potency from the fact that both the elements and the operations of the algebra are endowed with direct geometric intepretation.
