Ethnography is a branch of anthropology and the systematic study of individual cultures. It explores cultural phenomena from the point of view of the subject of the study. Ethnography is also a type of social research that involves examining the behavior of the participants in a given social situation and understanding the group members' own interpretation of such behavior.

Ethnography is a form of inquiry that relies heavily on participant observation. In this method, the researcher participates in the setting or with the people being studied, often in a marginal role, to document detailed patterns of social interaction and the perspectives of participants within their local contexts. It had its origin in social and cultural anthropology in the early twentieth century, but has, since then, spread to other social science disciplines, notably sociology.

Ethnographers mainly use qualitative methods, though they may also include quantitative data. The typical ethnography is a holistic study and so includes a brief history, and an analysis of the terrain, the climate, and the habitat. A wide range of groups and organisations have been studied by this method, including traditional communities, youth gangs, religious cults, and organisations of various kinds. While, traditionally, ethnography has relied on the physical presence of the researcher in a setting, there is research using the label that has relied on interviews or documents, sometimes to investigate events in the past such as the NASA Challenger disaster. There is also ethnography done in "virtual" or online environments, sometimes labelled netnography or cyber-ethnography.

The term ethnography is from Greek (ἔθνος éthnos "folk, people, nation" and γράφω gráphō "I write") and encompasses the ways in which ancient authors described and analyzed foreign cultures. Anthony Kaldellis loosely suggests the Odyssey as a starting point for ancient ethnography, while noting that Herodotus' Histories is the usual starting point; while Edith Hall has argued that Homeric poetry lacks "the coherence and vigour of ethnological science". From Herodotus forward, ethnography was a mainstay of ancient historiography.

Tacitus has ethnographies in the Agricola, Histories, and Germania. Tacitus' Germania "stands as the sole surviving full-scale monograph by a classical author on an alien people." Ethnography formed a relatively coherent subgenre in Byzantine literature.

While ethnography ("ethnographic writing") was widely practiced in antiquity, ethnography as a science (cf. ethnology) did not exist in the ancient world. There is no ancient term or concept applicable to ethnography, and those writers probably did not consider the study of other cultures as a distinct mode of inquiry from history. Gerhard Friedrich Müller developed the concept of ethnography as a separate discipline whilst participating in the Second Kamchatka Expedition (1733–43) as a professor of history and geography. Whilst involved in the expedition, he differentiated Völker-Beschreibung as a distinct area of study. This became known as "ethnography", following the introduction of the Greek neologism ethnographia by Johann Friedrich Schöpperlin and the German variant by A. F. Thilo in 1767. August Ludwig von Schlözer and Christoph Wilhelm Jacob Gatterer of the University of Göttingen introduced the term into the academic discourse in an attempt to reform the contemporary understanding of world history.

According to Dewan (2018), the researcher is not looking for generalizing the findings; rather, they are considering it in reference to the context of the situation. In this regard, the best way to integrate ethnography in a quantitative research would be to use it to discover and uncover relationships and then use the resultant data to test and explain the empirical assumptions.

In ethnography, the researcher gathers what is available, what is normal, what it is that people do, what they say, and how they work.