While UI design is primarily about visual elements, understanding certain languages can be beneficial. HTML (HyperText Markup Language) is used to structure content on the web, CSS (Cascading Style Sheets) is used for styling and layout, and JavaScript enables interactivity. UI designers also use a variety of software and tools for creating and prototyping designs. These include vector graphics editors (like Adobe Illustrator), wireframing tools (like Balsamiq), and UI design and prototyping tools (like Sketch, Adobe XD, or Figma). However, the actual design work doesn't typically involve coding, unless the designer also works on the front-end development.