async function legen() {
  return "dary";
}

is the same as

const legen = async () => {
    return "dary";
}

is the same as

function legen() {
  return Promise.resolve("dary");
}

Usage

cool().then(
  function(value) { /* happy case code */ },
  function(error) { /* some error handling */ } // is optional
);

is the same as

let wait_for_it = await legen(); //

Gotchas:

• await can only be used inside an async function => on global lvl you must go with .then()
• [].forEach() does not work on arrays returned by async functions! Need to use for ... of loop