The document discusses the fundamentals of JavaScript as a single-threaded, non-blocking, asynchronous, concurrent language, highlighting its call stack, event loop, and message queue. It explains how JavaScript executes code using the V8 engine and addresses the concept of asynchronous callbacks to prevent blocking. Overall, it emphasizes the structure and execution flow of JavaScript in handling tasks one at a time, while managing concurrency.

1. JavaScript: Behind the scene
Presented By: Shubham Chaurasia

3. JavaScript is a
Single threaded
Non blocking
Asynchronous
Concurrent
language.

4. JavaScript have a
Call Stack,
an Event Loop,
a Callback queue (Message Queue),
some Other Api’s and
stuff.

5. Who executes JavaScript code ?

6. So, v8 do you have a
Call Stack,
an Event Loop,
a Callback queue (Message Queue),
some Other Api’s and
stuff.

7. I have a
Call Stack
And a Heap
WTF are those other things?
(Event Loop, Callback queue and Web API’s)

11. Single threaded
means
One Call Stack
One thread == one call stack == one thing at a time.

14. Blowing the stack!

16. Blocking
What happens when things are slow?

17. The Solution?
Asynchronous Callbacks
Here is the function.
Call me later maybe?

18. Asynchronous Callbacks and Call Stack

19. Concurrency and Event Loop
One thing at a time. Not Really