What UX designers actually do?

So, tell me, what exactly does a UX designer do? I understand they're involved in creating a great user experience, but what does that really entail? Are they just designers who focus on how things look, or is there more to it than that? How do they go about their work, and what skills do they need to succeed in this field? I'm really curious to know more about what UX designers do on a day-to-day basis.