What does "encryption" do to data?

Encryption takes readable data and scrambles it into an unreadable code using a mathematical algorithm and a key, so that anyone intercepting the data without the correct key just sees meaningless characters. When you send a password or make an online payment, encryption protects that information as it travels across networks, and only the intended recipient, holding the matching key, can unscramble it back into its original, readable form.

Encryption does not make the internet faster; in fact it adds a small amount of processing overhead, though modern systems make this negligible. It also doesn't delete data permanently; deletion and encryption are entirely separate operations, with encrypted data still fully recoverable by anyone who holds the right key.

The padlock icon you see next to a website address in your browser indicates that your connection to that site is encrypted, which is why security experts warn against entering sensitive information on sites lacking that icon.