The scientific study and reconstruction of the human past through the systematic recovery of the physical remains of man's life and cultures. Artifacts, structures, settlements, materials, and features of prehistoric or ancient peoples are surveyed and / or excavated to uncover history in times before written records. Archaeology also supplements the study of recorded history. From the end of the 18th century onwards, archaeology has come to mean the branch of learning which studies the material remains of man's past. Its scope is, therefore, enormous, ranging from the first stone tools made and fashioned by man over 3 million years ago in Africa, to the garbage thrown into our trash cans and taken to city dumps and incinerators yesterday. The objectives of archaeology are to construct cultural history by ordering and describing the events of the past, study cultural process to explain the meaning of those events and what underlies and conditions human behavior, and reconstruct past lifeways. Among the specialties in the field are: archaeobiology, archaeobotany, archaeozoology, and social archaeology. Modern archaeology, often considered a subdiscipline of anthropology, has become increasingly scientific and relies on a wide variety of experts such as biologists, geologists, physicists, sociologists, anthropologists, and historians. The methods appropriate to different periods vary, leading to specialized branches of the subject, e.g. classical, medieval, industrial, etc., archaeology. archeology (from "archaia," ancient things, and "logos," science, knowledge, or theory)