Atheism is the lack of belief in a god or higher power. This only refers to the existence of god or more. This does not refer to anything else but that. In fact, calling yourself an atheist is about as broad as calling yourself human, or calling yourself a male or female (which is one reason why I don't like to call myself that). All it means is that one thing. It doesn't give you any more information than that. If you want to know what an atheist believes, ask them. If you want to know what I, as an atheist or a human or a male, believe then just ask me.
personally I believe in the earths power.. when we die and are burried or our ashes scattered we become fertilizer to put it bluntly our "energy" returns to the planet from which we fed. so I believe in science
I am an atheist. I believe in knowledge and learning. I believe in logic and reason. I believe in cookies and milk. I believe in being a good son, grandson, brother, uncle, nephew, etc. I believe that classic rock is great music. I believe it is better to fix the problems in this world than to hope for a better world in the afterlife. I believe that Episodes IV, V, and VI were better than Episodes I, II, and III. I believe that eating right and exercising is the best way to stay healthy. I believe in equal rights before the law, regardless of race, creed, or sexual orientation. I believe it's better to write someone a letter than to send them a text or an e-mail. I believe in being kind to service workers and in always leaving a good tip. I believe all myths have important lessons to teach us, but they are still just myths. I believe it's better to feed the hungry and heal the sick than to cut taxes for the wealthy. I believe in holding doors for strangers. I believe tomorrow will only be better if we work to make it so. I believe religion should be taught in church and science should be taught in science class. And finally... I believe it's time for lunch.
Be careful how the word is defined. "I believe I'll have a caramel macchiato" is something you'll hear theists and atheists alike saying. "I believe some immaterial part of me survives my death" is a kind of belief unique to theists.
All atheist means is a lack of belief in a god or gods. That is it. - - Everyone has a belief in something, but that is not necessarily a theology. I believe that you should do your best no matter what. I believe much of what wickedpissah stated in his answer. - - As for those who said an atheist believes in science, that is also incorrect. Science does not require a belief in it to be true. Science is there in everything we do.....from the food you eat to the air you breathe. Science is a fact not a theology.
Atheists don't believe in supernatural beings. Is that what you were asking? I believe in gravity, although I don't know 100% what gravity is, only what it does. Considering there have been and are hundreds of religions, the chance that one civilization guessed right (assuming there IS a right guess) is extremely low probability. For all we know, the Buddhists and reincarnation are true and everything else false. Who really knows.