Explanation : The Critical Path Method or CPM is a network analysis technique concerned with planning and controlling of complex, but routine projects. Simply, Critical path method is generally used for the projects whose time duration is known with certainty and also the amount of resources required for the completion of the project is assumed to be known. The Critical Path method is deterministic in nature, since the required amount of resources and the time needed for the completion of the whole project is known, and is mainly used in the construction projects. This method was developed by Du Pont Company and the Univac Division of Remington Rand Corporation as a technique for controlling the maintenance of chemical plants.