JavaScript is dynamically typed language.. it is the de facto language of the web.
You can use it primary to write Browser and/or Web server application.
Understanding Functions and objects.
How to write Functions, create objects, interact with HTML DOM …
Scope in every programming language including JavaScript designates the accessibility/visibility and lifetime of variables and Functions.
Callback is function passed as argument or stored in variable which is called at later time.
closure is a function that returns a function which continues to have access to the local environment as long as it is active.
== is used to compare two variables, === compares two variables and their types
Prototype is the mechanism by which any object/class inherits features from other objects/classes.
