Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript JavaScript and the DOM (Retiring) Responding to User Interaction The Event Object

Phuc Le
Phuc Le
5,182 Points

Event parameter question

In Functions as Parameters video, teacher passed a parameter into the callback function like this:

exec((something) => {
console.log(something);
}, 'Hi, there');

something parameter was assigned by string 'Hi, there', but in The Event Object video, event parameter was not assigned by anything, so is event global variable?

1 Answer

Steven Parker
Steven Parker
229,786 Points

The event parameter is passed to the handler by the system.

When an event occurs, the system creates an event object and passes it as a parameter to the event handler.