Glossary
Dataverse
Dataverse is Microsoft's cloud database for the Power Platform, with enforced relationships, row and field level security, proper data types and auditing. It is licensed per user and is not included with Microsoft 365.
It is the right answer when your data has genuinely outgrown SharePoint lists: enforced relationships, row-level security a list cannot express, or auditing in the data layer rather than in whatever application writes to it.
It is the wrong answer when it has not, because per-user licensing for a register of forty rows is not recoverable. Starting on lists and moving later is a known, bounded task; paying for two years is not.