The arguments object is a collection of parameter values pass in a function. It's an Array-like object because it has a length property and we can access individual values using array indexing notation arguments[1] but it does not have the built-in methods in an array forEach,reduce,filter and map.
It helps us know the number of arguments pass in a function.

We can convert the arguments object into an array using the Array.prototype.slice.

function one() {
  return Array.prototype.slice.call(arguments);
}

Note: the arguments object does not work on ES6 arrow functions.

function one() {
  return arguments;
}
const two = function () {
  return arguments;
}
const three = function three() {
  return arguments;
}

const four = () => arguments;

four(); // Throws an error  - arguments is not defined

When we invoke the function four it throws a ReferenceError: arguments is not defined error. We can solve this problem if your envinroment supports the rest syntax.

const four = (...args) => args;

This puts all parameter values in an array automatically.