Card sorting involves users, or stakeholders of a website ‘sorting’ cards into groups that make the most sense to them. The cards represent content on the website.

An open sort (where users define the groups they put cards into) can be used to help create information structure from the user’s perspective. A closed sort, (where groups are defined that the users must put the cards into) tend to be used to test or validate an existing design.

A good reason to use card sorts is that they are a quick and costeffective way of gauging what a small sample of your users think. This process provides insight into the user’s mental models. Much of the value of card sorting comes from hearing why the user sorts the cards in the way that they do.