The Stack Exchange button, also known as the Stack Exchange™ MultiCollider SuperDropdown™, refers to the button that appears at the top right of all Stack Exchange 2.0 sites.

Some history of the popular alternate name.

When the Stack Exchange button is pressed, a dropdown menu is displayed listing, in order:

  1. The site that you are currently on, and its meta site or parent non-meta site.
  2. A list of sites that you have associated accounts with, ordered by most reputation to least reputation.
  3. An alphabetized list of all Stack Exchange sites with a search bar at the top.

The Stack Exchange™ MultiCollider SuperDropdown™