These instructional materials provide an orientation to hydraulics for use at the postsecondary level. The first of 12 sections presents an introduction to hydraulics, including discussion of principles of liquids, definitions, liquid flow, the two types of hydraulic fluids, pressure gauges, and strainers and filters. The second section identifies and describes three types and three functions of accumulators. The third section covers the functions and size of reservoirs. The fourth section outlines pump classifications, types of pumps, and nine rating and selection factors. The fifth section reviews hydraulic piping, tubings, and requirements for line selection. The sixth section describes directional control valves. The seventh section describes check valve functions and pilot-operated check valves. The eighth section presents types of pressure control valves. The ninth section covers pilot-operated pressure control valves. The 10th section explores flow control valves. The 11th section describes cylinders: elements, types, types of construction and mounting; selection; and cushioning. The last section reviews the three types of hydraulic motors, eight rating and selection factors of motors, and seven types of rotary actuators. Examples are provided for each section of the guide. A quiz is included at the end of each section, except section nine. Answers to all of the quizzes are found at the end of the guide. (NLA)