A Decision Support System (DSS) is a computer-based information system that supports business or organizational decision-making. It can help managers at different levels of an organization make decisions by providing tools to access and analyze data. A DSS combines data, documents, knowledge, and models to help identify and solve problems. It has evolved over time from focusing on data and models to also include knowledge and documents. A DSS is made up of a database, models, and a user interface. It aims to support semi-structured and unstructured decision-making.