a characteristic graph that indicates how much energy a pump must supply (Total Head - AH) to generate a specific flow rate Q for a particular system
                                                            
                                                     
                        
                                                
                        
                        
                            a set of head/flow data which describes the performance at a given node in a piping system
                                                            
                                                     
                        
                                                
                        
                        
                            A description of what the pump is required to perform. The pump will pump where the system curve intersects the pump curve.