The WBS field contains work breakdown structure (WBS) codes, which are alphanumeric codes you can use to represent the associated task's position within the hierarchical structure of the project. WBS codes are similar to outline numbers, except that you can edit WBS codes or apply a specific WBS format, or mask. WBS codes are also unique; you can only have one WBS code per task.
There are several categories of WBS fields.
Data Type Text
WBS (task field)
Entry Type Calculated or entered
How Calculated The default WBS code is the task's outline number. You can type or define a format for your own custom WBS code. If you type a WBS code, you can modify it at any time. If you clear a WBS code, the field value returns to the outline number. If you define a WBS code format, or mask, Microsoft Office Project completes the WBS field with a value corresponding to the task's outline level and WBS code mask. You can only enter a WBS code that matches the WBS code mask you defined.
Best Uses Using the WBS field is most helpful if your company uses a specific WBS code system for project management. Add the WBS field to a task view when you want to display, enter, or change the WBS codes for tasks.
Example You have set up your project with the WBS code mask that your department uses, and you actually want to view and print reports that refer to the WBS codes with all tasks. You add the WBS field to the Task Sheet view.
Remarks To set up the WBS code mask, on the Project menu, point to WBS, and then click Define Code. Use the WBS Code Definition dialog box to set up the code mask for different levels and to enter any applicable prefix to the WBS code.
WBS (assignment field)
Entry Type Calculated
How Calculated Microsoft Office Project assigns the assignment's WBS code according to the associated task's WBS code. The default WBS code is the task's outline number.
Best Uses Add the WBS assignment field to the Task Usage or Resource Usage view when you want to display the WBS code associated with a task assignment. This can also help you identify tasks by number.
Example When reporting on assignment progress, you prefer to use WBS codes rather than task names. You add the WBS field to the Resource Usage view.