This is a cost-effective technique for identifying usability problems in prototype products and processes. The technique encourages design teams and users to collaborate in order to identify usability issues and their solutions.
Users work with a prototype as they carry out tasks set by the design team.
During this procedure users explain what they are doing by talking or thinking-aloud . An observer records unexpected user behaviour and the user s comments regarding the system. The observer also actively questions the user with respect to their intentions and expectations. This provides qualitative information concerning any difficulties that the users experience and the features or interface elements which give rise to these problems. The method is applicable in the early phases of the design cycle once a prototype is available for evaluation or at a later stage when an existing product is to receive further development.