Creativity is goal-directed thinking that produces novel and useful ideas. It involves both convergent and divergent thinking. Convergent thinking finds single solutions, while divergent thinking generates many possible solutions. There are various stages of creativity including preparation, incubation, illumination, verification and revision. Wallas proposed five stages: preparation, incubation, illumination, verification and revision. Creativity can be obstructed by fears of rejection, but it simplifies complexity by finding elegant solutions.