Project plan is a management summary document that gives the essentials of a project in terms of its objectives including justification. In the same time it will include how the objectives are to be achieved though out the project by summarizing the activities, systems, skills and resources needed to achieve the short, medium and long term aims of the project. So it describes how all the major activities under each project management function are to be accomplished. This is a contract between the Project Manager, Executive Sponsor, Project Team and other management of the enterprise associated or affected by the project.
The purpose of the project plan is to provide important information required by stakeholders and project team members to define, execute, and close a project. This document evolves throughout the successive stages of the project life cycle. So this document used to guide both project execution and project control though out the project.
There are number of benefits of using a project plan such as,
Enables to evaluate the performance of the team as a whole.
A documentation for legal, regulatory and historical use of the information
Aids to compare the planned work against the amount of work team actually performed.
Enables to judge the work of the team as a gestalt effort while allowing to see the changes that need to make.
Aids to reduces cost, both in terms of money and of human effort.
Team members will get to know their role and responsibilities
Specification of data collection and quality control