Knowledge discovery is a research area within the field of data mining and machine learning that focuses on extracting useful and meaningful knowledge from large and complex datasets. It involves the use of various techniques and algorithms to analyze data, identify patterns, trends, and relationships, and make predictions or decisions based on the discovered knowledge. Knowledge discovery is used in various domains such as business, healthcare, finance, and science to uncover valuable insights and improve decision-making processes. The ultimate goal of knowledge discovery is to help organizations and individuals make more informed decisions and achieve their objectives more effectively.