Difference between event types ITEM_TRASH and DELETE

Hi,  There are few event types with names that means the same. I did some testing, but couldn't pinpoint the difference. For example, the structure of "source" object/json seems to be different for ITEM_TRASH and DELETE. It looks like those have to be handled separately with its own logic. Is this understanding correct? Could you please clarify?

ITEM_UPLOAD vs UPLOAD,

ITEM_TRASH vs DELETE,

ITEM_MODIFY vs EDIT