array sort by alphabetical javascript

users.sort((a, b) => a.firstname.localeCompare(b.firstname))

//sort array alphabetically
objArray.sort(function(a, b) {
   return a.localeCompare(b);
});

var fruits = ["Banana", "Orange", "Apple", "Mango"];
fruits.sort();

//sorts arrays of numbers
function myFunction() {
  points.sort(function(a, b){return a-b});
  document.getElementById("demo").innerHTML = points;
}

arr.sort(function(a, b) {
    return a === b ? 0 : a < b ? -1 : 1;
  });