Password manager: one breach, one account

A password manager generates a long, random password for each service you use and stores it in an encrypted vault, unlocked by one master password. The key contrast is reuse versus uniqueness: if you reuse the same password across ten sites and one gets hacked, an attacker can log into all ten. With a manager, even if a site is breached, only that one password is compromised, and the rest remain safe. This turns the biggest human weakness—remembering dozens of passwords—into a non-issue.

In an exam, watch out for questions that imply a password manager is a single point of failure: it is not, because the master password is never stored online and the vault uses strong encryption. Another trap is confusing a password manager with a browser's built-in password saver—the latter often lacks encryption and syncs insecurely. A quick elimination trick: if an option says "write passwords in a notebook" or "use the same password for low-risk sites," those are wrong because they reintroduce reuse or physical theft risk.

To remember this, think of a key ring: one master key opens a box that holds many different keys, each for a different lock. If one lock is picked, the others are untouched. In an exam, ask yourself: does this option prevent a single breach from spreading? If yes, it likely involves a password manager.