UX design is the design of the user experience on a resource. This is one of the first steps in product development, the primary task of which is to build logic and convenience in the practice of using the resource by the end user. UX-design also determines the emotional impact of interaction with the product, forms the impression of use and the algorithm for further interaction. Therefore, the main task of UX-designer, is to think thoroughly where and how to place the functionality, put the entrance to the personal account, on the right or on the left, the number of steps in the user's execution when reaching a specific task, such as a newsletter subscription or making an order, also determined by understanding how successful the operation was... All this is the task of UX-designer.
UI-design is the implementation of UX-design externally. With UI-design a resource becomes clear to the user purely intuitively, attractive appearance and maximum ease of use. It is achieved by applying graphics and implementing them in the controls, whether it be buttons, checkboxes, pictures, fonts, color schemes and different color images.
The direct duty of UX/UI designer is to help the user to achieve the goal with which he came to your site, application or program. It is from the result of the UX / UI designer user decides definitively on the further interaction with the resource, for example, "like it or not like it," to buy or not to buy.