A toggle is a small piece of wood or plastic that is sewn to something like a coat or bag and pushed through a loop or hole to fasten it. On computers and some machines, toggles are used to switch between functions. In software, they are used to implement features and roll them out to users at different times. Feature toggles are a useful tool for developers and designers as they work to make their applications more accessible, performant, and user friendly. When designing a toggle, it is important to consider the proximity of the label and the color to the action it will perform on the system. This will help the user understand how a toggle is currently functioning, and which action to take. It is also important to consider the societal and cultural implications of color when designing a toggle.

In addition to their ability to control the rollout of new functionality, toggles are a great tool for supporting agile development practices. They allow product teams to validate features with a small segment of their audience before they are rolled out to the entire production environment. This way, they can be sure the feature will be well received before making a major investment in it.

While using toggles in a production environment is an efficient and convenient way to manage change, they can be expensive to maintain and support. Toggles create thousands or millions of database calls when flipped, and they can impact performance as well if left unchecked for long periods of time. To avoid these costs, it is recommended to limit the number of toggles in a production environment and to remove them as soon as they are no longer needed.