This chapter explores what the science of ethnology is trying to do, and how it hopes to contribute to the general sum of knowledge. It is the business of ethnology to study the nature of the different groups called as nations, tribes, or what not, into which Man has come to be divided. Each of these groups, even the simplest tribe of Australia or Tierra del Fuego, has a complex character and shows features of culture, such as language, social organisation, religion, arts and crafts, each of which forms a special subject of study. It is its business to discover how it has come about that man presents his vast diversity of speech and thought and custom, and to find the explanation of the many points of similarity which constantly present themselves throughout the diversity. The chapter illustrates the nature and aims of the science by a brief record of its history, a history even of very short duration.