A toggle is a switch that enforces a mutually exclusive state, either on or off. It’s a key concept in software and hardware design and it can be seen in all sorts of places. For example, when you press the Caps Lock or Num Lock keys on a keyboard, those are toggles that enable or disable specific functions. You can also see them in settings menus in most applications.

The word toggle originally meant a pin passed through the eye or bight of a rope to fasten it around a stay, mast, etc. It is still used as a verb to indicate switching between two positions, such as when you toggle back and forth between screens during a video chat with a friend:

Toggle switches are often used in software to enable or disable features. This is a common technique because it allows us to make changes to the user experience without needing to deploy an entirely new version of the application. It can be done for both front-end and back-end features.

However, there are some challenges with toggles. For one, they can cause cognitive problems when the current state is not obvious to users. Additionally, they can be difficult for people with color vision deficiency to use if designers are not careful to select high-contrast colors for states and use clear labeling to explain the current state of a toggle.

Using toggles is also a challenge for accessibility, particularly in Web environments. If a designer simply copies toggle code off the Internet, they will most likely create an inaccessible experience for screen readers and other assistive technologies. It is important to understand these challenges and consider how to make toggles as accessible as possible.

Another challenge with toggles is that they can be cumbersome to manage at scale. When a large number of toggles are used, it can be difficult to keep track of their state in source control. For this reason, many organizations choose to move Toggle Configuration into some sort of centralized store, such as an existing application DB or a dedicated toggle configuration system.

Depending on the complexity of the application there are a variety of different approaches to managing Toggle Configuration. For example, a simple but less dynamic approach is to hardcode the configuration into source files using a preprocessor’s #ifdef feature. This is an acceptable solution for some applications, but it does require an ongoing commitment to modifying and updating the toggles in all source code that is being deployed. In most cases, this is not a viable solution for features with many different toggle configurations and is better suited to a more advanced toggle management tool.