A toggle is a switch that has two positions: on and off. You might use one to change the brightness of a lamp or to switch between streaming and map views in a mobile app. You can also toggle between screens as you video chat with two friends at once, or adjust the volume on your music player.

In software development, the word toggle has a similar meaning, and it is a key component of Agile methodologies. Rather than working on feature branches in the traditional waterfall model, teams can hide features behind toggles until they are ready to be released (or at least made public).

The best way to understand a toggle is by looking at how it is implemented in code. There are a number of ways to manage the configuration of toggles in software, from more dynamic approaches that allow for continuous re-configuration to static methods that only work at deployment time and cannot be reverted. The most important thing is to have a clear process in place to manage the lifetime of your toggles.

Some teams will add a task to their backlog to remove a toggle when it is no longer needed, while others will put “expiration dates” on their toggles so that they automatically fail a test (or even refuse to start an application) once the date has passed. These kinds of processes are essential to ensuring that your team’s inventory of toggles is kept as low as possible.

In addition to a solid process for managing the lifetime of a toggle it is also important to ensure that you are using toggles in the right places. For example, a toggle should not be used in form fields where the user needs to click a Save or Confirm button for changes to take effect. In these cases, a checkbox is a better choice because it does not require a confirmation.

Toggles are particularly well-suited to settings and preferences that only need to be ON or OFF. They are often the preferred control for these types of changes on mobile because they are easier to tap and take up less screen space than two radio buttons.

Toggle is a great tool for teams looking to speed up the development and testing of new features. It is also a powerful technique for helping to keep the quality of an application high by keeping its features stable and preventing the need for constant manual regression testing. However, it is essential that the team has a strong process in place for removing toggles as they expire or are no longer needed, in order to avoid an over-abundance of idle flags. By doing this, a team can make sure that the software they release is always of the highest quality.