In simple words, what is ABA?

Applied Behavior Analysis is a science committed to designing, implementing interventions, and evaluating environmental factors to produce socially significant changes in the individual life. ABA uses reinforcement procedures to increase the occurrence of desired behaviors and challenging behaviors are analyzed to understand their function (why are they occurring?). Then, more helpful behaviors are taught to replace those defiant by reinforcing new behaviors. The main goal is to work on meaningful behaviors for the individual and his surroundings.