A prototype is the work product of the prototyping phase in the interface design process. It is a model of the final interface that is in the process of being designed. Since it is a simulation of the end product, it is used for user testing to identify pain points and improvements earlier in the design process.
The fidelity of a prototype denotes its level of detail. In this answer, we'll talk about prototypes that are low fidelity in nature.
A low-fidelity prototype is a representation of the interface drawn physically, such as on paper or a whiteboard. In such a prototype, connections between pages are also shown by physically sketching them. This is done by drawing a directed line from the clickable element to the window shown after clicking. For example, a login button drawn on paper will be linked to a login window by an arrow, establishing a clickable connection.
Low-fidelity prototypes are used in the early stages of the interface design process. The primary purpose of such prototypes is to help get feedback and identify requirements before moving to the detailed design phase.
The following image illustrates a low-fidelity prototype of the product page of an e-commerce website.
The advantages of low-fidelity prototypes are explained below.
Since low-fidelity prototypes do not contain all the features, creating them takes less time. They are also easy to make as the designer does not have to focus on the aesthetics or the working of every function. A low-fidelity prototype can be quickly sketched during a brainstorming session and thus does not waste much time in case of rejection.
Low-fidelity prototypes are not that costly as they use few resources. A pen and paper are the only things needed to create a low-fidelity prototype. Thus, they save up on many costs and can be made anywhere by anyone.
Low-fidelity prototypes focus a lot on ideas instead of aesthetics, which helps foster creativity. Building a low-fidelity prototype is usually a team effort that also encourages team-building.
Since low-fidelity prototypes are made on paper or whiteboards, changes are just a matter of erasing and redrawing. Not much time or effort is wasted in trying out different ideas by making adjustments to the prototype.
Low-fidelity prototypes are simple, low-tech sketches of the prototype. Therefore, a person does not have to be experienced with multiple tools to make such a prototype.
The disadvantages of low-fidelity prototypes are explained below.
Low-fidelity prototypes are of lesser quality than high-fidelity ones. This is because they do not carry a lot of functionality. They are just simple sketches of how the final interface will look. Therefore, they lack some quality as they may not represent all the features.
In-depth user testing results can not be generated by using a low-fidelity prototype. This is because they can not be used to represent the interaction of the end-user with the final product. Thus, they can not collect accurate data on human performance for user testing reports.
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