What is Difference Between PERT and CPM ?

Difference Between PERT and CPM

CPM	PERT
stands for CRITICAL PATH METHOD	Stands for Project Evaluation and Review Technique
CPM uses activity oriented network.	PERT uses event oriented Network.
Durations of activity may be estimated with a fair degree of accuracy.	Estimate of time for activities are not so accurate and definite.
It is used extensively in construction projects.	It is used mostly in research and development projects, particularly projects of non-repetitive nature.
Deterministic concept is used.	Probabilistic model concept is used.
CPM can control both time and cost when planning.	PERT is basically a tool for planning.
In CPM, cost optimization is given prime importance. The time for the completion of the project depends upon cost optimization. The cost is not directly proportioned to time. Thus, cost is the controlling factor.	In PERT, it is assumed that cost varies directly with time. Attention is therefore given to minimize the time so that minimum cost results. Thus in PERT, time is the controlling factor.
Activities are represented as nodes or circles	Activities are represented by arrowed lines between the nodes or circles