In general, three types of HPLC pumps are available. Syringe pumps because of their suitability for small bore HPLC columns are becoming more popular. The traditional reciprocating piston pumps are the most popular because of their accuracy and wide range of application. Constant pressure pumps are also available. The syringe pumps deliver mobile phase to the column by way of a motorized screw cylinder. The constant pressure pumps are feed from a gas cylinder and the reciprocating pumps are covered by the animations.