Psychology is the scientific study of the human mind and its functions, especially those affecting behavior in a given context. Psychology is very important to design because designers can grasp what their customers want from psychology, either the price is low, or the unique and distinctive product.
In design, the most commonly used colour and shape are also related to psychology. They can create a state of mind for people. For example, the colour black affects the mind and body by helping to create an inconspicuous feeling, boosting confidence in appearance, increasing the sense of potential and possibility, or producing feelings of emptiness, gloom, or sadness.
Huaiyuan Liu CCA1103 