Doing Business As, also known as (DBA) is used when you are going to conduct business under a different name other than your personal name or the official business name.
It’s similar to operating your business under an assumed or fictitious name. Often times businesses will do this to launch a new product line or create a separate business identity. Note, that a DBA does not provide liability protection!
If you are a sole proprietor and your name is John Brown but your business name will be Brown Automotive, then you would file a DBA. If you already have a corporation or LLC, and you wanted to product test a new item under a different company name you could file a DBA.