async function

async function asyncFunc1(){
  return 42;
}

asyncFunc1()
  .then(function(response){
    output.innerText = response;
  })
  

promise in async

async function asyncFunc2(){
  let innerPromise2 = new Promise(
    function(res, rej){
      setTimeout(function(){
        res("promise 2 result");
      }, 2000); // 2 seconds
    }
  );
  return innerPromise2;
}

asyncFunc2()
  .then(function(response){
    output.innerText = response; // resolve
  })
  

await in async

async function asyncFunc3(){

  let innerPromise3 = new Promise(
    function(res, rej){
      setTimeout(function(){
        res("promise 3 result");
      }, 2000); // 2 seconds
    }
  );
  
  let result = await innerPromise3;
  
  output.innerText = result; // resolve
  
}

asyncFunc3();