Vault
In plain terms
A tool for securely storing and managing secrets.
Going deeper
HashiCorp Vault centrally stores secrets, encrypts data, and issues short-lived dynamic credentials with fine-grained access control. It's a leading secret-management system.
Under the hood
Dynamic secrets, leasing, and revocation reduce long-lived credential risk; supports encryption-as-a-service.
Examples
Secret storage, dynamic database credentials, encryption, access control.
Think of it like...
Like a high-security bank vault that issues temporary, trackable access keys on demand.