The project schedule is a fairly broad and all encompassing concept that while seemingly easy to grasp, must truly be mastered in order for all members of the project staff, from the project management team all the way up to the project management team leader to effectively manage the project in a capable manner from start to finish. The project schedule typically will include all elements of the project from the pre-planning stages of the project through all ongoing project processes that may take place during the active project period, to any and all project related process that may occur at the conclusion and or closing stages of the project. The project schedule, as a project related input/.output mechanism, typically keeps careful track of any and all planned dates for the performance of particular schedule activities, as well as any predetermined dates that are expected to be met and followed up on in regards to the implementation of any particular project milestones.
This term is defined in the 3rd and the 4th edition of the PMBOK.