Levels, or stages, refer to distinct phases in a process or development. They help categorize progress, making it easier to understand and manage complex systems. For example, in education, students advance through levels such as elementary, middle school, and high school, each representing a different stage of learning and maturity. In various fields, levels can indicate proficiency or achievement. In video games, players progress through levels that increase in difficulty, requiring new skills and strategies. Similarly, in project management, stages like planning, execution, and closure help teams track their progress and ensure successful completion of tasks.