What password protection should mean
Many note apps advertise password protection, but the details differ enormously. In some products, the password unlocks a screen while the note itself sits readable on the company servers. In others, the password is the actual encryption key, and nobody except you can decrypt the content.
The second model is called zero-knowledge, and it is the version worth wanting. When the browser encrypts the note before anything leaves your device, the password protection is real cryptography rather than a lock icon.
What to look for in a free tool
You should not need an account, a credit card, or an email address just to write a private note. A good free option works instantly, encrypts locally, and explains plainly where the key lives.
Check the practical features too: does the note expire, can you limit how many times it opens, and does it behave well on mobile? Those details decide whether the tool fits real situations like sending a password to a family member or storing a recovery code temporarily.