# JavaScript Closure
Before everything, we need to know JavaScript has 2 types of variables (based on Variable Scope to categorize), global & local variable !!
# Concept:
function having access to parent scope, especially function can use variable which is defined outside of the function!!!
Example:
var value = 0; // variable declared outside of function outputValue
function outputValue() {
function plus () { value = value + 1 }; // value can be used inside the function
plus();
return value; // will return 1 as result
};
outputValue();
Another Example for scope of this:
var person = {
name: 'damon',
printPersonAttribute() {
console.log('this.name: ', this.name); // damon
function unableToPrintPersonAttribute() {
console.log('nested this.name is not working: ', this.name); // undefined
};
unableToPrintPersonAttribute();
},
}
person.printPersonAttribute();