This Module is Module 4 in a 13 module eCourse series on Stats, Cardiac Cycle, Basic Echo Exam. For information on the full Pediatric Echocardiography, please click here. This module will use a question and answer session to discuss the basic hemodynamics which are important to understanding congenital heart disease. These concepts are relatively basic but important for the student to fully comprehend before proceeding. The session relates predominantly to the topic of congenital heart disease-- and also discusses some confusing terminology as it is sometimes applied and mis-applied to this topic.