A project schedule is commonly referred to as the project plan but technically the schedule is a project document not the project plan. A project plan is the how and when the project will deliver the projects objectives. It will describe how the project will work and be conducted.
The schedule will have the breakdown of the activities which need to be completed, when those activities will start and end, and who is responsible for those tasks. Schedules can provide information regarding duration and sequence. The schedule can be laid out to display what activities to be completed before other tasks can start. The project schedule should also provide a status of the activities. The status could be not started, on track, at risk, and a host of other indicators. As the project manager, keeping the project on schedule is vital to the success of the project and the schedule is the document to ensure tasks are accounted for and tracked.
The project schedule should also be used as the project’s baseline so when changes are made to say scope, the project management plans will have the original requirements.