How this function works???

Question

How this takes value of a, b? How this works
var a = [33, 4, 1111, 222];
a.sort(); // Alphabetical order: 1111, 222, 33, 4
a.sort(function(a,b) {
return a-b;
});
a.sort(function(a,b) {return b-a});

Answer 1

https://www.w3schools.com/js/js_array_sort.asp

Answer 2

Thank you so much Ulisses Cruz