The motile bacteria are able to move by Cilia, Pili, Fimbriae, Flagella

The most common mechanism used by bacteria to swim through liquid media is the flagellum. The bacterial flagellum consists of 3 major domains: an ion driven motor, which can provide a torque in either direction; the hook, a universal joint, which transmits motor torque even if it is curved; and the filament, a very long structure, which acts as a propeller, and behaves differently depending on which way the motor turns.