User Interface (UI) is an integral part of User Experience (UX) Design. Where UX Design is the why of a product, UI Design is the how of a product. UI Design is the process of making software or computerized device interfaces with a focus on looks and style. Although UI and UX Design are often put together, both require separate skill sets, skills that are highly advantageous, but just aren't being taught in school.
Here are a few real-word examples of jobs and people working in this industry right now.