gistfile1.txt

function sayHi() {
  console.log("hi");
}
function blackhole() {
  while (true) {
    1 + 1;
  }
}
setInterval((function () { sayHi() }), 1000);
setTimeout((function () { blackhole() }), 5000);
// You'll see "hi" 4-5 times and then nothing, because
// JS is single-threaded and can't execute in parallel.