MySQL Server has an extensive collection of SQL modes which control a range of behavior ranging from compatibility modes for other RDBMS dialects (ANSI_QUOTES, PIPES_AS_CONCAT) to security (NO_AUTO_CREATE_USER) to explicit storage engine selection (NO_ENGINE_SUBSTITUTION) to restricting lossy implicit data conversions (STRICT_TRANS_TABLES, etc.). …
Source: mysqlserverteam.com