Alistair Chisholm

TIL #1 – Arguments Vs Parameters

Arguments and parameters are often confused and referred to interchangeably. They are two very different things.

I'll try to make the distinction. A parameter is a variable defined inside the function and is used to reference an argument once it has been passed in to the function. An argument is a value that is declared when you call a function.

To understand the difference consider this very simple example function and its usage:

function sum(param1, param2) {
  return param1 + param2;

sum(10, 20);

In this function, param1 and param2 are function parameters, and the values passed to the function (10 and 20) are arguments.