UX design refers to user experience design while UI design stands for User interface design. Both of these are crucial to an IT product and need to work closely together. The UX designer is the champion of a Users needs and is concerned with the overall feel of the product. On the other hand, the UI designer takes care as to how the product is laid out. He/she is responsible for designing each screen or page with which a User interacts and ensuring that the UI visually communicates the path that a UX design has laid out.