Dynamics is a branch of physics developed from classical mechanics that deals with the study of forces and their effects on motion, as well as the effects of various physical quantities such as mass, energy, and so on.
Dynamics is the study of how a physical system may develop or change over time as a result of various factors, as well as the causes of those changes.
Newton developed the fundamental physical laws that govern physics dynamics. Dynamics can be understood much more easily and efficiently by studying Newton's system of mechanics.
Dynamics, in particular, is closely related to Newton's second law of motion.