PMBOK terminology for WBS structure

[pixelfreak]

I'm trying to get clear in my head, the terms that PMBOK uses for project structural elements. In the glossary it includes:

• Work Breakdown Structure (WBS)
• Work Breakdown Structure Component
• Work Package

When you read the definitions things are pretty clear. WBS is a tree structure, Work Breakdown Structure Components are the nodes (branches) in the tree and Work Packages are the leaf nodes.

The PMBOK glossary includes other terms which can be thought of as structural elements. These are:

• Activity
• Project
• Sub Project
• Project Phase
• Sub Phase
• Task

How best should we think about these elements in relation to each other ? For example do these elements follow a strict hierachy ?

Project -> Sub Project (optional) -> Phase -> Sub Phase (Optional) -> Many layers of activity -> Work Package

Would it be fair to say (with the exception of "project") that each of these are a type of Work Breakdown Structure Component ?

Or is "Activity" a synonym of "Work Breakdown Structure Component" with things like phase, subphase and sub project being types of activities ?

[matt.betros]

Spot on! I'd think that WBS Component is everything in the WBS Structure (Tree). The Work Packages are the lowest levels of the WBS with Activities underneath them.