What is a baseline source?
A baseline source is a container that holds all the baselines for a specific group of items.
You can add a baseline from a project, set, folder, filter, release, or individual items. Adding a baseline creates the source automatically. The source is created in the tree and contains the new baseline. A source can't exist without a baseline.
If a source already exists when a new baseline is created for the same set of items, the baseline is added to that source. Otherwise, a new source is created and added to the top of the tree.
Key to the baseline tree
Green database icon — Source
White box wrapped in gray — Baseline
Individual Items — Default source name when multiple items are selected at the time the baseline is created.
B1-04/27/2020 — Example of a default baseline name (baseline number and date it was created). Baseline name is editable as needed.
FYI
You can create a new baseline from an existing source.
Deleting a baseline source deletes all the baselines it contains.