This is the difference between func() and func. The first parameter of setTimeout is func. If func() is used, it is equivalent to its return value being the first parameter.
For example:

function test（）{ console.log('this is test!'); return function () { console.log('this is return!'); } } setTimeout(test(), 1000);

roughly equivalent to:

console.log('this is test!'); setTimeout(function () { console.log('this is return!'); }, 1000);

The first parameter passed is executed immediately, not the function name

has nothing to do withPromise. When you executesetTimeout(resolve('World'), ms);, the browser has automatically executedresolve('World'), for example:

var test = function(value){ console.log(value); } setTimeout(test('hello') , 2000);

At this time thetestis executed immediately.

The first parameter of setTimeout must be a function

A function

A function

(Why so many people don’t understand)

setTimeout(resolve, ms, 'World');whereresolveis a function, so this section behaves normally
setTimeout(resolve('World'), ms);whereresolve('World' )is not a function, what determines it is the return value type ofresolve, but in any case,resolvehas already been executed whenregistering the timer, so naturally there is no delay effect

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The following answers are invalid: I did not review the question carefully. .
There is generally no difference.

Just! ! ! !

IE browser has a problem with its support forsetTimeout(resolve, ms, 'World'). (It seems that IE

Reference materials: (see the note with yellow background inside)

WindowOrWorkerGlobalScope.setTimeout()