Linguistics is the scientific study of how languages are learned, processed, used, and structured, it investigates why and how languages change and their status in social life. Linguistics is important to social and cognitive psychology, native and foreign language teaching at all levels, artificial intelligence and computer science, communications, sociology and anthropology, and historical accounts of human civilization. Linguists work in colleges and universities, language instruction and educational planning, communications industries (including publishing), translation services, and cross-cultural business and government agencies.