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← Security & recovery
03 / Foundations · 2 min

One secret should not open every door

Reusing a password lets a breach at one service create risk at another.

In 30 seconds

  1. Use a unique, strong password for each account.
  2. A password manager helps create and keep different passwords.
  3. Protect the manager and understand its recovery options.
Make it concrete

Imagine the same key opening your school locker, home and office. A copied key then affects every door.

  1. 01Unique password
  2. 02Manager
  3. 03Recovery
Concept diagram · simplified for learning
Check your understanding

Is a long password safe to reuse on unrelated websites?

Learning paths →

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Sources reviewed: 13.09.2026