A project milestone is an important point or event in the project timeline that signifies important progress or achievements. It is a reference point used to measure the progress of a project and can be used to help identify when a project is running behind schedule. Milestones are usually specified in a project plan or project charter and can be used to track the progress of a project. In most cases, project milestones are related to the completion of a specific project task or the achievement of a particular goal. Milestones are often used to measure progress against expectations and to ensure that key deliverables are completed on time. Milestones also serve to inform stakeholders of the progress of a project, as well as to provide an indication of the remaining work that needs to be completed for the project to be successful. Project milestones are a crucial part of any project and serve an important role in helping to ensure the successful completion of the project