Explained In detail as given below
- Using Asynchronous code, we are able to execute multiple things/JavaScript call at the same-time without locking the DOM or main thread.
- You can define a global variable for call-back method.
- You can use call-back method because JavaScript is lexical scoped and can't define a variable in the call-back methods.
- The response and data come from the parent's call-back method.
- etc..
Thank you!
For more detail you can go
http://stackoverflow.com/questions/11233633/understanding-asynchronous-code-in-laymans-terms
http://stackoverflow.com/questions/11233633/understanding-asynchronous-code-in-laymans-terms