What is the difference between dynamic and static characters?

Dynamic characters change throughout the course of the work, while static characters stay the same or undergo very little change. A dynamic character undergoes important internal or mental changes because of the action in the plot or because of the actions of other characters.

A static character's personality or outlook does not change throughout the events in the story's plot. Static characters should not be confused with flat or one-dimensional characters. Perfectly interesting characters can still be static characters; unlike the dynamic characters, the static characters remain constant and unaffected by the course of events that takes place in the story.