SQL commands are primarily classified into DML, DDL, and DCL. DML (Data Manipulation Language) encompasses commands that alter data, such as INSERT, UPDATE, DELETE, and SELECT. UPDATE, a quintessential DML command, is employed to modify existing records within a table. CREATE and ALTER fall under DDL (Data Definition Language) commands, which are used to define or modify database structures like tables. DROP is another DDL command utilized for deleting tables or databases. Consequently, UPDATE is the sole DML command present in this context.