This article is from the Atheism FAQ, by mathew firstname.lastname@example.org with numerous contributions by others.
Unfortunately, the popularity of a belief has little to do with how
"correct" it is, or whether it "works"; consider how many people
believe in astrology, graphology, and other pseudo-sciences.
Many atheists feel that it is simply a human weakness to want to
believe in gods. Certainly in many primitive human societies, religion
allows the people to deal with phenomena that they do not adequately
Of course, there's more to religion than that. In the industrialized
world, we find people believing in religious explanations of phenomena
even when there are perfectly adequate natural explanations. Religion
may have started as a means of attempting to explain the world, but
nowadays it serves other purposes as well. For instance, for many
people religion fulfils a social function, providing a sense of
community and belonging.