Question

How come I can say:

var myFunction = function() {
   setTimeout(myFunction, 1000);
}
myFunction();

Why does the function call in the setTimeout not require parentheses, but the last line does?

Answer 1

myFunction is a function

myFunction() calls the function and yields whatever value the function returns.

The purpose of setTimeout is running code after some time elapses. You need to pass just the function to it (so setTimeout can itself call the function when appropriate) because if you called the function (with the parenthesis) before passing it to setTimeout it would execute now instead of after 1 second.