function change value of variable code example

Example 1: how to change a variables value in javascript

var variable = 10;

function start() {
  variable = 20;
}
console.log(variable + 20);

// Answer will be 40 since the variable was changed in the function

Example 2: change a variable outside a function js

var global = "Global Variable"; //Define global variable outside of function

function setGlobal(){
       global = "Hello World!";
};
setGlobal();
console.log(global); //This will print out "Hello World"