Toggle is a form of on/off control usually found in hardware such as the Caps Lock or Num Lock keys or software settings. It’s a type of binary switch which is either On or Off and can be easily flipped.
Toggles can be used to update preferences, settings or other kinds of information. They are most useful when they help users make quick and confident decisions. Toggles should be clearly labeled, use standard visual design elements, and deliver immediate results. It’s also important that designers consider a toggle’s color to avoid confusion and ensure it is easy to identify its current state. In addition to ensuring that the color contrasts well, designers should also evaluate any societal or cultural implications of the choice of colors for an On or Off toggle.
Many teams use Feature Toggles as part of their CI/CD pipeline to deploy and test experimental features. A Feature Toggle is like a Canary Release but instead of being triggered by a build it’s triggered by a request from a user and can be updated at any time (though it’s not recommended to change a toggle in-flight as this can be disruptive).
Regardless of the configuration used it’s best for teams to test all the possible combinations of toggle states including any that will eventually be live in production. This helps to prevent surprise regressions. In the case of Experiment Toggles it’s also helpful to test the system with and without the experiment configured so that you can see the impact on the overall performance.