The document discusses question answering systems. It describes how QA systems can automatically respond to natural language questions by retrieving information from knowledge bases using information retrieval and natural language processing technologies. It also discusses problems in human resources like lack of full-time HR staff and low speed. Neural networks are described as a machine learning method inspired by the human brain that can predict outputs. Recurrent neural networks, LSTM, and sequence-to-sequence models with attention mechanisms are discussed as techniques for building QA systems.