Software Process Model: Prototyping

In all the software process models I’ve shared, the spiral and the unified process models have used prototyping as a way to complete the phases. So, really, what is prototyping?

Software prototyping is the activity of creating prototypes of software applications. Prototypes are either a representation of the idea, or an incomplete version of the software product being developed. In other words, a prototype is a working model of a software or an idea with some limited functionality.

The five (5) types of prototypes in software development and the discussion for each:

1. Illustrative
2. Exploratory
3. Throwaway
4. Incremental
5. Evolutionary

ILLUSTRATIVE PROTOTYPE

As the most basic of prototype, these are either drawings on a napkin, brief slideshow or just index cards with components drawn to them. These prototypes are usually in low fidelity and disposable image that is just used to share an idea and use as a way to weed out bad ideas. This also just gives the development team some guidance for creating solutions.

EXPLORATORY PROTOTYPE

Exploratory Prototyping allows the team to focus on what the product look and feel but it allows a bit of development so the team will have an idea of the effort they need to exert to completely build the project. This prototyping usually allows the product developers to study the feasibility of some product idea so they can scope out the whole development process.

THROWAWAY PROTOTYPE

Let’s say the product developers have already created a prototype and has already a working version of the software, but with minimum features. The first product usually has various problems and when clients check, the team will realize they want a different version from the first. Instead of building further from the first prototype, the team decided to build a completely new version, based from the feedback and approach being learned from the first one.

The throwaway prototype gives the developers an opportunity to learn from past mistakes and for the business side of the project, it allows the client and the management to stop the product release, and improve the product further with a totally different version.

INCREMENTAL PROTOTYPE

This type of prototype allows the product with limited functionalities to be used until the final product version. The key idea is to have a working software for each successive prototype, to which can be released on each iteration as a version of the software product.

In this type of prototyping, the product is developed in a triage system. Here, each system’s components are assessed and given priority. Based on that priority, the development team creates the product from the ground up. The most critical feature are a must-do and becomes the core features, while those aren’t absolute priority are tagged as a can-do feature added after each iteration, or each version of the product. Since the product’s features are prioritized, it is then becomes easy for the software product manager to map out and plan the development with the team.

EVOLUTIONARY PROTOTYPE

In this prototyping, the development team begins creating all the features in basic form, then just refine or evolve them, over time. Here, the users will be using an early version of all the features and the developers will just build on successive prototypes of the working features until these are much more easier or flexible to use. In this way, the product evolves from a rudimentary working prototype to something feature rich and robust.

DIFFERENCES BETWEEN PROTOTYPES

With illustrative, exploratory and throwaway prototyping, the initial set of work done after set aside to create a newer version of the product. Though for some software development processes, developers use illustrative prototypes to kick off the working product. On the other hand, the incremental and the evolutionary prototypes build upon the minimum set of features, and works to add or build more even after the final product is released in the market. In these types of prototyping, the working software from the initial build is already shown at regular intervals to the client for feedback and improvement.

In the end, the core idea behind prototyping is to gain feedback on versions of your product, right? So here, we see why prototyping is really important.

References:

University of Alberta (2020). Software Processes and Agile Practices. [Coursera Course] under the Software Product Management Specialization. Taken November 2020.

Poulette, B. (2020). Prototyping. [Video]. Embedded under the course study videos under the Week 2 of the Software Processes and Agile Practices Coursera Course. Taken November 21, 2020.