A toggle is a switch or lever that moves between two positions, such as on and off. A toggle can have different appearances in each of its states to help people understand its state at a glance. It can also be a piece of hardware, like a pin passed through the eye of a rope to fasten it. The word toggle can also refer to the action of switching back and forth between two positions, as when someone is sleeping in REM and non-REM sleep cycles.
The most important aspect of a good toggle is the design of its visual cues. The simplest and quickest way to do this is to have each state of a toggle represented by a distinct color. Choosing high-contrast colors for toggles will make it easy for users to perceive their current state at a glance. It’s also recommended to use state descriptors (e.g., ‘On’ or ‘Off’) next to each toggle.
Toggle configuration can be managed in a number of ways, ranging from very simple approaches to highly sophisticated ones. Using static comments to hardcode the configuration of a toggle is simple, but it doesn’t allow for dynamic re-configuration. Instead, many teams opt to store the configuration of a toggle in some type of centralized system—either an existing application DB or a separate toggle management UI. These solutions offer the advantage of allowing teams to dynamically change a toggle configuration by rolling out a new release. This makes them very appropriate for Ops Toggles or other features that will require a periodic re-configuration.