It's really quite simple; perhaps that's why some people don't get it. Atheism is a specialised subset of scepticism, one dealing exclusively with theism. It has nothing to say about any other subject falling within the scepticism remit, except insofar that they may impinge upon theistic claims. Thus even if a person believes in the ghost of Martian Elvis nipping down in a flying saucer to conspire with Reptilian Freemason Obama about setting up the New World Order controlled from a secret base inside the hollow Earth, if s/he lacks a belief in a god they're an atheist. Note correct usage of the contraction.
At the age of five, Skagra decided emphatically that God did not exist. This revelation tends to make most people in the universe who have it react in one of two ways - with relief or with despair. Only Skagra responded to it by thinking, 'Wait a second. That means there's a situation vacant.'
