does javascript sort require number code example

Example 1: javascript sort

var names = ["Peter", "Emma", "Jack", "Mia", "Eric"];
names.sort(); // ["Emma", "Eric", "Jack", "Mia", "Peter"]

var objs = [
  {name: "Peter", age: 35},
  {name: "Emma", age: 21},
  {name: "Jack", age: 53}
];

objs.sort(function(a, b) {
  return a.age - b.age;
}); // Sort by age (lowest first)

Example 2: sort by ascending javascript

const months = ['March', 'Jan', 'Feb', 'Dec'];
months.sort();
console.log(months);
// expected output: Array ["Dec", "Feb", "Jan", "March"]