Asynchronous programming is the act of performing specific tasks at a particular time, and these are often referred to as operations. Programmers should ensure that processes get finished and eventually have their work done within a specific time.
Callbacks are simply pieces of code that get called back after some operations have been completed. A callback is a function passed as an argument to another position, and the other process then calls the callback at some point during its execution.
This allows asynchronous programming, where code can be executed in parallel without blocking the main program thread. Callbacks are often used in event-driven programming, where a program waits for user input or network events.
Callbacks are usually passed as anonymous functions but can also be defined as named functions and passed by reference. In addition, inline functions can also be used as callbacks.
Asynchronous programming is a great way to improve the speed and performance of your code. You can ensure that specific tasks are completed by using callbacks before moving on to other code sections.
The easiest way to understand asynchronous programming is to compare it with synchronous programming. Synchronous programming is what we are all used to. You write your code and wait for it to finish before you get the following line of code. This is called blocking.
However, as you might have noticed, in the real world, you sometimes want to do two things simultaneously. To be able to do so, we use asynchronous programming. How does this work?
An asynchronous function will not wait for its execution to finish before executing the following line of code. It will give you back control, allowing you to continue in your script (as if the code had been synchronous).
Then when the asynchronous code has finished its execution, it will automatically resume your script where it left off (as if the code had been synchronous) and give you back the control.
Asynchronous programming is a form where code execution does not wait for the completion of another process before beginning.
This type of programming can be used when you want to do two tasks simultaneously. It can also be used to improve performance by using system resources.