Atheism is a non-belief in God. In your KS3 Religious Education lessons, you will be learning about the various different religions people believe. But what about those who have no religious beliefs?
If you take a look at a list of the most populous religions in the world, you might find a category for non-believers, or atheists. One such list has a category for "secular/agnostic/atheist", which, with 1.1 billion members, falls in third place behind Islam (1.2 billion) and Christianity (2.1 billion). This inclusion is intended to point out that a sizeable number of people have no religious beliefs.
What do these terms mean? An atheist is someone who does not believe in any supernatural beings or explanations for phenomena.