Card sorting is a user research method used to help organize and classify content or information. In a card sorting exercise, participants are given a set of cards, each with a piece of content or information written on it. They are then asked to sort the cards into groups or categories that make sense to them. This can be done using physical cards, or using a digital tool such as a website or mobile app. The goal of card sorting is to understand how users think about and organize information, and to use this information to design user-friendly navigation and content structures. Card sorting can be a valuable tool for designers, as it provides insights into how users expect to find and access information, and can help identify potential issues or inconsistencies in a design. Card sorting can be conducted with individual users or with groups, and can be an open or closed activity, depending on the goals of the research.