Atheism, in a broad sense, is the rejection of belief in the existence of deities. In a narrower sense, atheism is specifically the position that there are no deities. Most inclusively, atheism is simply the absence of belief that any deities exist. Atheism is contrasted with theism, which in its most general form is the belief that at least one deity exists.
The term atheism originated from the Greek ἄθεος (atheos), meaning "without gods", which was applied with a negative connotation to those thought to reject the gods worshipped by the larger society. With the spread of freethought, skeptical inquiry, and subsequent increase in criticism of religion, application of the term narrowed in scope. The first individuals to identify themselves as "atheist" appeared in the 18th century. Today, about 2.3% of the world's population describes itself as atheist, while a further 11.9% is described as nonreligious.Between 64% and 65% of Japanese describe themselves as atheists, agnostics, or non-believers, and 48% in Russia. The percentage of such persons in European Union member states ranges as low as single digits in Italy and some other countries, and up to 85% in Sweden.