A password vault is a secure software tool designed to store and manage passwords and other sensitive information, such as credit card details, secure notes, or access keys. The purpose of a password vault is to help users securely store complex passwords and easily retrieve them when needed, reducing the risk of weak passwords or security breaches.

Key Features of a Password Vault:
1. Encryption: Password vaults encrypt your stored data, ensuring that even if the vault is compromised, the information inside remains protected.
2. Master Password: Access to the vault is protected by a single master password or biometric authentication.
3. Password Generation: Many vaults can generate strong, random passwords for accounts.
4. Cross-Device Syncing: Modern vaults often allow access from multiple devices, such as phones, tablets, and computers.
5. Auto-Fill: They can auto-fill login forms, saving time and enhancing convenience.
6. Secure Sharing: Some vaults allow users to securely share access to accounts without revealing the actual password.
7. Alerts: Advanced vaults can notify users of potential security breaches or when passwords need updating.

Using a password vault significantly improves online security by encouraging unique, strong passwords for every account and reducing reliance on memory or insecure storage methods.