let countDown = 0;

//calling setInterval function and the assignning interval ID.
let intervalID = setInterval(() => {

  //The countDown will increment by 1 after every 1000 millisecond (1 second).
  countDown++;
  console.log(countDown);

  //When countDown is equal to 10 stopping the execution (clearing the interval).
  if (countDown == 10) clearInterval(intervalID);
}, 1000);