Toggle is a control used to change the state of an application feature. It can be found in everyday technology devices such as phones or software applications and provides a simple way to switch between states without having to modify code.

Unlike checkboxes or radio buttons, toggle switches have a unique form factor and use movement and color to convey their state. This makes them more cognitively accessible than other controls. However, it’s important to consider how they’re implemented and how they communicate their state. If a toggle uses low-contrast colors, it may be difficult for some users to tell which way the switch is positioned. It’s also important to consider cultural and societal implications of the colors you choose, as they can have different meanings for some groups of people.

Toggles are often used as a means to conduct multivariate testing. By enabling the toggle to flip between different code paths and tracking the aggregate behavior of each cohort you can make data-driven optimizations to things like the purchase flow in an ecommerce site or the Call To Action wording on a button.

Using a toggle can also be a good way to introduce a new feature to your product. By setting a toggle to be off by default and then enabling it through a message or UI update you can test the impact of a feature without having to make the change permanent. However, savvy teams will recognize that Feature Toggles are inventory that comes with a carrying cost and actively seek to keep their inventories as low as possible by adding a task to the backlog to remove a toggle once it has been rolled out and no longer needed.