Single Acting and Double Acting hydraulic cylinders What s the difference

Welded Double Acting Hydraulic Cylinder Bore 2.5 Stroke 30 Rod 1.5 Retracted 38 Extended68 Pin Size 1 Port Size SAE 8 Column Load 11,700 lbs Work Pressure 3500 PSI Color Black. Hydraulic cylinder welded double acting 2.5 bore 30 stroke cross tube 2.5x30 compatible equipment type backhoe loader.