The user interface is a critical part of any software product. When it’s done well, users don’t even notice it. When it’s done poorly, users can’t get past it to efficiently use a product.
To increase the chances of success when creating user interfaces, most designers follow interface design principles. Interface design principles represent high-level concepts that are used to guide software design. In this article, I’ll share a few fundamental principles. These are based on Jakob Nielsen’s 10 Usability Heuristics for User Interface Design, Ben Shneiderman’s The Eight Golden Rules of Interface Design, and Bruce Tognazzini’s Principles of Interaction Design. Most of the principles are applicable to any interactive systems — traditional GUI environments (such as desktop and mobile apps, websites) and non-GUI interfaces (such as voice-based interaction systems).
The principles are:
- Place users in control of the interface
- Make it comfortable to interact with a product
- Reduce cognitive load
- Make user interfaces consistent
1. Place users in control of the interface
Effective interfaces instill a sense of control in their users. Keeping users in control makes them comfortable; they will learn quickly and gain a fast sense of mastery.
Make actions reversible (be forgiving)
This rule means that the user should always be able to quickly backtrack whatever they are doing. This allows users to explore the product without the constant fear of failure — when a user knows that errors can be easily undone, this encourages exploration of unfamiliar options. On the contrary, if a user has to be extremely careful with every action they take, it leads to a slower exploration and nerve-racking experience that no one wants.
Perhaps the most common interfaces where users have the ‘Undo/Redo’ option are text and graphics editors. While writing text or creating graphics, ‘Undo’ lets users make changes and go back step-by-step through changes that were made. ‘Redo’ lets users undo the undo, which means that once they go back a few steps, they are able to move forward through their changes again.