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JavaScript Asynchronous Programming with JavaScript Asynchronous JavaScript with Callbacks Callbacks Review

Posted by J Tan
J Tan
11,847 Points

If a function is called from another function but is not passed in as a callback, is the parent function asynchronous?

If a function is called from another function but is not passed in as a callback, is the parent function asynchronous? Are callbacks a prerequisite for asynchronous functions?

1 Answer

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

While callbacks are a common communication method for asynchronous functions, just having one does not make a function asynchronous. Plus you can have asynchronous functions that don't take callbacks (example: "fetch").

And simply calling a (normal) function from inside another one does not make either one asynchronous.

J Tan
J Tan
11,847 Points

What is the benefit of using callbacks vs calling another function within the body of the parent function? Is it for readability because the callback is listed as one of the function arguments?

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

A function called in the body will always be the same function. But with a callback, the caller tells the function which other function to call, so it might be different each time.