Welcome to the Treehouse Community
The Treehouse Community is a meeting place for developers, designers, and programmers of all backgrounds and skill levels to get support. Collaborate here on code errors or bugs that you need feedback on, or asking for an extra set of eyes on your latest project. Join thousands of Treehouse students and alumni in the community today. (Note: Only Treehouse students can comment or ask questions, but non-students are welcome to browse our conversations.)
Looking to learn something new?
Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today.
Steven Parker210,872 Points
A "callback" is just a function passed to another function as an argument.
The other function will then call the "callback" function to indicate some event, usually at a later time.
You'll see plenty of examples of these when you work with event handlers, timers, AJAX requests, and other operations where the program must respond to things which will happen in the future.