A milestone is a significant event or point in a process that marks progress or achievement. It is often used in project management to indicate key stages in a project timeline. For example, completing a major task or reaching a specific deadline can be considered a milestone, helping teams track their progress and stay organized. In a broader context, milestones can also refer to important life events, such as graduating from school or celebrating a birthday. These milestones often symbolize personal growth and development, serving as markers of time and achievement in an individual's life.