How to sort an array of integers correctly

I am surprised why everyone recommends to pass a comparator function to sort(), that makes sorting really slow!

To sort numbers, just create any TypedArray:

var numArray = new Float64Array([140000, 104, 99]);
numArray = numArray.sort();
console.log(numArray)

By default, the sort method sorts elements alphabetically. To sort numerically just add a new method which handles numeric sorts (sortNumber, shown below) -

var numArray = [140000, 104, 99];
numArray.sort(function(a, b) {
  if( a === Infinity ) 
    return 1; 
  else if( isNaN(a)) 
    return -1;
  else 
    return a - b;
});

console.log(numArray);

Documentation:

Mozilla Array.prototype.sort() recommends this compare function for arrays that don't contain Infinity or NaN. (Because Infinity - Infinity is NaN, not 0). This was solved by Sergio Abreu's edition, handling NaN and Infinity inside the function.

Also examples of sorting objects by key.

Just building on all of the above answers, they can also be done in one line like this:

var numArray = [140000, 104, 99];
numArray = numArray.sort(function (a, b) {  return a - b;  });

//outputs: 99, 104, 140000