What's a work type?
A classification of actual work. For example, a professional services enterprise may define work types such as Analysis, Design, and External Training.
Use work types to determine whether expenditure items are billable and to classify cross-charge amounts into cost and revenue.
When you create or import expenditure items, the default work type is inherited from the associated task. Tasks, in turn, inherit work type values from parent tasks and ultimately from the project. Project types determine the default work type value for projects and project templates.