The System Development Life Cycle (SDLC) is a conceptual model used in project management that describes stages in developing an information system project. It includes planning, analysis, design, implementation, and maintenance phases. During planning and analysis, requirements are defined and the system is evaluated. In design, options are considered and blueprints are developed. Implementation involves completing tasks such as testing. Maintenance provides ongoing support and improvements. The SDLC provides an organized process to develop systems efficiently and meet user needs.