Hi @yit ,

Basically, they are the same thing. Not so long ago,  they renamed DLT (Delta Live Tables) to Lakeflow Declartive Pipelines. So I think from now on in all materials you will see new name for this library: pipelines (instead of dlt)

 guess they didn't managed to change old name in all their docs yet, so you can see here and there old name for that library.