You use Expense Categories when you create consumption registration lines for Expenses on a Work Order.
In order to register expenses (hours) for the work done by Contractors, you must set up at least one Expense Category. If you use several Contractors, you may want to set up an Expense Category for each Contractor to for cost tracking purposes. An Expense Category used for a Contractor must be related to a Resource.
Refer to the article Expense Categories to learn how to set up Expense Categories.
The screenshot below shows an example with three Expense Categories set up for Contractors. Each Expense Category relates to a specific Resource (shown in the Type No. and Type Description fields).