A design system is
a set of standards to manage design at scale by reducing redundancy while creating a shared language and visual consistency across different pages and channels.
Therese Fessenden, Nielsen Norman Group
They are used in website and product design and include things like a style guide and a component library which contain reusable user interface elements. They are often talked about as providing benefits to design teams such as consistency, maintainability of the design elements. But I think they can offer so much more.
Each of those visual elements in the component library should have guidance about what to and what not to use it for, and more interestingly, could also have the results of analytics and research on it’s performance in a number of scenarios.
An email sign-up component, for example, could have information about how well it converts when at the top of the page, in the middle and at the bottom. Then, when designing a web page the decisions about which components to use and where to place them can be based on the goals for the page rather than what looks visually pleasing.
Proflowers is one if the highest converting website with a 26.5% conversion rate, according to Practical Ecommerce. The home page, like many websites, is made up of visual components of navigation, banner image with a call to action, a quick ordering option, selection of best sellers, etc. Using a design system, the team that manages to website would be able to apply what they learn about how each of these elements performs on other pages. This approach changes the idea of a page as the unit of analysis for conversion rate to the combination and ordering of the components.
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