WordPress salts are randomly generated cryptographic keys used to enhance the security of WordPress websites. They are stored in the wp-config.php file and work by adding extra layers of protection to stored passwords and authentication cookies. By using unique salts, WordPress ensures that even if an attacker gains access to the database, deciphering user passwords becomes significantly more difficult. Salts help prevent common attacks such as brute force and cookie theft by making hashed values unpredictable. It is recommended to periodically change these salts to maintain optimal security for your WordPress installation.