The document provides an overview of software development methodologies. It defines the software development lifecycle (SDLC) as a systematic process for planning, creating, testing, deploying and maintaining software. Common SDLC phases include planning, requirements analysis, design, implementation, testing and deployment. It then defines software development methodologies as structured approaches that can improve efficiency, quality and collaboration. Example methodologies discussed include waterfall, agile (scrum and kanban), prototyping (spiral model), rapid application development, and iterative and incremental processes. The waterfall model is described as a traditional linear approach, while agile values flexibility, collaboration and customer satisfaction.