An information system is a group of components that collect, organize, store, and communicate information to help organizations operate, manage their resources, and compete in the marketplace. There are different types of information systems that support various organizational levels, including transaction processing systems, office automation systems, knowledge work systems, management information systems, decision support systems, and executive support systems. The systems development life cycle is the process used to plan, create, test, and deploy information systems and includes steps like system planning, analysis, design, implementation, testing, and maintenance.