What type of card sort allows users to create their own grouping scheme?

An open card sort is a technique in which participants organize items into groups that make sense to them, without predefined categories. This allows users the flexibility to create their own grouping schemes based on their understanding, preferences, and experiences. By using an open card sort, researchers gain insights into how users think about the relationships between different concepts or items, which can inform the design of information architecture or navigation structures.

This method contrasts with other types of card sorts; a closed card sort has predetermined categories that users must sort items into, limiting their ability to classify items in ways that may feel more intuitive to them. A hybrid card sort combines elements of both closed and open card sorts but does not allow for complete freedom in categorization. A guided card sort provides users with more structure or prompts within the sorting process, which again constrains their ability to freely categorize as they might in an open card sort. Thus, the open card sort is distinct in allowing users to define their organizational logic, leading to richer user-centered insights.