# connector-development

Nathan Gille

02/28/2022, 4:23 PM
Why do some sources have stream specific schemas if airbyte also requires a configured catalog? What is the point for both?
Hi @Nathan Gille, you can consider a configured catalog as a subset of a source catalog. ConfiguredCatalog contains the list of the streams a user wants to sync, a Catalog contains the full list of streams a source exposes. Does it make sense to you?
Okay yes that makes sense to me, but why have both? Also, under source-<source-name> there is a schemas folder. What are those schemas used for?