What are Programme Evaluation and Review Technique?

PERT (Programme Evaluation and Review Technique):

It is a technique used for controlling and scheduling the projects where activities are subject to considerable degree of uncertainty within the performance time. Initially it was used through the US Ballistic Fleet Missile Project of the US Government into designing and producing main weapon systems for the US Military Establishment. It is because not like CPM that is determinative, the point of reference of PERT is probabilistic and its application is primarily for Research and Development projects. It is used to calculate the variance in project duration and also to find out the probability of completing a project by a specified date. Unlike CPM, uses merely one time evaluate for each activity, PERT utilizes three time estimates that are optimistic time and probably time as well as pessimistic time. The fundamental tool used in PERT method is flow plan or the network. Network comprises a series of related activities and events. The network therefore drawn shows how different activities of a project depends upon each other and which certain activities have to be completed before another can start.