User experience, UX, describes the overall quality of someone's interaction with a page or product: whether it's easy to use, fast, clear, and genuinely helps them accomplish whatever they came to do. In SEO specifically, UX and search performance have grown increasingly intertwined, since Google's own ranking systems now directly incorporate signals, Core Web Vitals, mobile-friendliness, safe browsing, that are essentially measurements of experience quality.
It's a genuinely broad concept, covering everything from page load speed and layout stability to navigation clarity, readable typography, and whether a call to action is actually easy to find and use. Good UX and good SEO tend to reinforce each other rather than compete: a fast, clear, well-organized page that helps visitors accomplish their goal is also the kind of page search engines want to rank, since both are ultimately measuring the same underlying thing, whether the page actually serves the person who arrived at it. Treating UX and SEO as separate disciplines pulling in different directions usually means one team is optimizing against the other rather than toward the same shared goal.
