An Atheist asserts a disbelief in a God(s) and/or the supernatural.I respectfully disagree Parli. Another broader definition of atheist leaves room for belief in the possibility of the existence of God, simply stating that no real evidence exists to support such belief.
An Agnostic leaves room for the possibility that those things may exist.
Technically, you are right nvgnbk. However, we agnostics sometimes tend to be a little more open to the possibility than atheism tends to allow for. I used to consider myself atheist for the reasons you mentioned, but I felt it to be a bit too confining.
j