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WBS is nothing but Work Breakdown Structure. It is mainly used in Project System (PS) module. Tcode: CJ20N. For any project defined we must have atleast one WBS. Within this WBS we can have networks. Networks are nothing but the series of activities. Material are used to perform the activities.
WBS is a hierarchical and incremental decomposition of the project into phases, deliverables and work packages. It is a tree structure, which shows a subdivision of effort required to achieve an objective; for example a program, project, and contract.utually exclusive: In addition to the 100% rule, it is important that there is no overlap in scope definition between different elements of a work breakdown structure.