ABSTRACT
A plan is the listing or visual display that results when all project activities have been subjected to estimating, logical sequencing and time analysis. For all practical purposes, some form of network analysis is usually the preferred method for preparing a plan, but bar charts provide better visual aids and can be more effective for communicating plans to project personnel. Bar charts are not only easy to draw or construct and interpret but are also readily adaptable to a great variety of planning requirements. When compared with bar charts, critical path networks provide the more powerful notation needed to show all the logical interdependencies between different jobs. Several network systems emerged during the second half of the twentieth century, but these all fit within one or other of two principal groups, determined by the method of notation: Activity-on-arrow system and precedence networks.
