Akismet

Akismet is a spam detection and filtering service developed by Automattic, the company behind WordPress. It is primarily used to identify and block spam comments on blogs and websites. When a visitor submits a comment, Akismet checks it against a vast database of known spam and various algorithms to determine whether the comment is likely to be spam or legitimate. If a comment is flagged as spam, it is either moved to a separate spam folder or blocked entirely.