The word ‘naturalism’ has a bewildering array of uses in philosophy. Roughly speaking, it connotes pro-scientific attitudes and approaches. This article introduces the subject of naturalism by sketching a history of pro-scientific attitudes and approaches in philosophy, from their origins in the early modern period through to the present day. It then distinguishes a number of distinct families of naturalism: metaphysical, logico-linguistic, epistemological, and methodological. The resulting taxonomy encompasses a plurality of loosely related views rather than a number of variations on a single clear and unified theme.