GIS (Geographic Information Systems) is a system that integrates hardware, software, and data to capture, store, analyze and display spatial or geographic data. It allows users to view, understand, question, interpret, and visualize data in many ways that reveal relationships, patterns, and trends. Key components of a GIS include hardware, software, data, people, and methods. The document then provides examples of each component and defines common GIS terms like cartography, data types, topology, and benefits of using GIS for spatial analysis and decision making.