you know that javascript is a single thread and asynchronous language

single thread

single thread languages make use of only one CPU at a time
on the other side other languages are multi-threaded
it's that many processes can hanppend at the same time

Essentially meaning that it can only perform one function at a time and if a function takes some time to finish , such as an HTTP request , it would literally block the user from interacting with the webpage

what is the process

reference

but there are disadvantages is that communication happends incorrectly or out of order ,
the system can crash.

Asynchronous & Synchronous

Asynchronous

• process can happend out of order.

Synchronous

• process can happend order.

What is the order of Execution

• the Callstack
• the Event Loop
• the Task Queue
• WebAPIs/External Resources