I have a general question on a Data Warehouse Architecture. I have heard a lot of a Staging and a Production, so that data should be loaded via SSIS first into a staging dwh and then via SSIS to the Production environment.

But is there any difference? I mean is it only a "copy" of the production data warehouse (to do some quality checks on data before pushing to production?) or of the source data in a different model or (different schema)?

From software development perspective i know that both are identical and the only purpose is to check the software version from all stakeholders and get the release to deploy on prod. Normally in the software case the staging is same (maybe only hardware sizing is different) to production.