This lecture covers the fundamentals of question answering systems, focusing on tasks, models, and limitations. It delves into the complexity of question types, answer types, and classical QA methods. The instructor explores the evolution from classical QA to modern approaches like Extractive QA and Generative QA, discussing their pros and cons. The lecture also touches on QA datasets like SQuaD and the evaluation metrics used in assessing QA systems. Additionally, it examines challenges such as synonymity, ambiguity, and multi-hop reasoning that remain in the field of question answering.