One of the beauties of software prototyping is the way that we can fine tune the level of ‘richness’ of the prototype to suit its audience.
We can create ‘wide and shallow’ prototypes, which are used to provide a broad impression of an entire system without implementing specific detail. These can be used to gauge the overall navigation, feel and ‘shape’ of a proposed system.
This approach is more common during the early stages of prototyping, where much of the fine detail has yet to be established. The ‘width’ refers to the scope of a system – for example, a ‘wide’ prototype of a payment system would generally include the full user interface, menus and such. However, being ‘shallow’ there would be very limited functionality built into the prototype. So, though htere might well be a full set of menus, they wouldn’t normally do very much, beyond perhaps opening placeholder forms or very simple navigation.
Contrast this with a ‘narrow but deep’ prototype, which is essentially a prototype with a far narrower scope but with increased functionality and detail.
This can be used to provide a very rich user experience of a particular slice of a system, with a very close approximation to that of a developed solution. This can include things like mock data, logic-based branching and all of the polish that one might expect in the end product.
Richer ‘deep’ prototyping tends to follow ‘wide and shallow’ prototyping. It needs a basic foundation to build in the richness of functionality, and that foundation is normally provided by an existing ‘wide and shallow’ prototype.
Of course, it’s not unusual to have ‘full feature’ prototypes, which incorporate both full scope (‘width’) and functionality (‘depth’) – but these are large and complex to create and are generally the preserve of high visibility, big budget developments.
More typically, creating a ‘wide/shallow’ prototype or two for basic requirements formulation and design, followed by some enhancements to key areas in terms of ‘depth’, provides enormous benefit to most projects.