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JavaScript Asynchronous Programming with JavaScript Asynchronous JavaScript with Callbacks Callback Functions Review

Posted by Hanwen Zhang
Hanwen Zhang
20,084 Points

What does invoke callback means here? what does it work as?

function makeMeal(meal, cb) { alert(Preparing ${meal}.); ; }

makeMeal('lunch', () => { alert('Finished the meal!'); });

1 Answer

Peter Vann
Peter Vann
36,427 Points

Hi Hanwen!

Invoke just means call/run/execute/trigger (that funtion), which is what () does.

For example: playSound(); is invoking the playSound function - much like hitting a 'PLAY' button on a CD player.

I hope that helps.

Stay safe and happy coding!

Hanwen Zhang
Hanwen Zhang
20,084 Points

Got it. Thank you Peter