An accordion, also known as an accordion-style layout is a web format in which a vertically-stacked list of headers can be clicked to hide or reveal the related content below.

The format, when clicked, folds out the way the musical instrument, an accordion would.

An accordion-style format may looking something like this:

Advantages of an accordion-style format are they:
- Minimize page scrolling meaning readers are more likely to see more content on page
- Allow users to easily scan the content
- Cater to readers' skimming behaviors

However, accordion-style formats do necessitate clicking into the header text to get more information, so aren't always ideal.

Before implementing this format on your site, it should always be tested.