The distinction between these two major categories is that collections credited to appropriation or fund accounts are offset within the account that contains the associated disbursements (outlays), whereas offsetting receipts are in accounts separate from the associated disbursements.
One class of items (collections credited to appropriation) is held a related disbursement account while the other (offsetting receipts) is not.
Both categories are types of cars.
A boy is swinging.
A woman holding an umbrella on a rainy day.
There is no person in the store.
An artist is painting a stop sign.
The young boy pushed the girl down really hard.
it's catching on, at least I think so