What is password hashing?
Runs your password through a one-way function and stores only the result, called a hash.
Store passwords exactly as typed, and one breach exposes every account. Well-built apps never store your password at all.
What it is
Password hashing runs your password through a one-way function and stores only the result, called a hash. It can't be turned back into the password.
How it works
When you sign up, the server adds a random value called a salt, hashes the two together, and saves the hash with the salt. When you log in, it hashes what you typed the same way and compares. It uses deliberately slow algorithms like Argon2 or bcrypt, so mass guessing is painfully slow.
Why it matters
The salt means two people with the same password get different hashes. And it's why a well-built site can reset your password, but never email it to you.
