A survey on question answering systems with classification

Question answering systems (QASs) generate answers of questions asked in natural languages. Early QASs were developed for restricted domains and have limited capabilities. Current QASs focus on types of questions generally asked by users, characteristics of data sources consulted, and forms of correct answers generated. Research in the area of QASs began in 1960s and since then, a large number of QASs have been developed. To identify the future scope of research in this area, the need of a comprehensive survey on QASs arises naturally. This paper surveys QASs and classifies them based on different criteria. We identify the current status of the research in the each category of QASs, and suggest future scope of the research.