The Project Management Plan (PMP) is a formal document that defines how a project will be executed, monitored, controlled and closed. It describes the actions needed to plan, integrate and coordinate project activities. The PMP is progressively elaborated throughout the project.
The scope management plan describes how the project scope will be defined, developed, monitored, controlled and verified. It helps reduce the risk of scope creep.
Developing the project schedule involves defining activities, sequencing them, and estimating activity durations. The critical path method (CPM) identifies which activities must be completed on time for on-time project completion and which activities have float or slack.