Context: Prototyping is an established practice within product and user interface design that is also used as a requirements engineering (RE) practice within agile development. Even so, there is a lack of theory on prototyping.
Aims: Our main research objective is to support practitioners in improving on their prototyping practices.
Method: We have designed a model that describes key aspects of the practice of prototyping. The model is based on a systematic mapping study consisting of thirty-three primary studies and on empirical data from twelve case companies. We validate and demonstrate the applicability of our model through a focus group at one company and through semi-structured interviews at eleven (other) startup companies.
Results: Our prototyping aspects model (PAM) consists of five aspects of prototyping, namely purpose, prototype scope, prototype media, prototype use, and exploration strategy. This model has enabled practitioners to discuss their prototyping practices in terms of the concepts provided by our model.
Conclusions: The model can be used to categorise prototyping instances and can thereby support practitioners in reflecting and improving on their prototyping practices.