User experience design is a growing field. This is due in large part to the rise of the internet and the growing need for digital experiences to be aligned well with users just like physical products have been designed to align well with physical users.
ux definition
Why is user experience design important? Well, if you want someone to use your website, you need to make sure you have made it usable. It needs to be tailored to the most common uses of your visitors. You wouldn't make a chair that everyone thinks is uncomfortable. So why would you make a website that is hard to navigate and interact with? That's the essence of user experience design.