Sychronous VS Asynchronous Javascript

Today, i'll be writing about Sychronous and Asynchronous Javascript.
Fistly, the definitions;
Synchronous tasks happen in order i.e you must finish the first job before moving on to the next. On the flip side, you can execute asynchronous jobs in any order or even simultaneously.

Asynchronous is a non-blocking architecture, so the execution of one task isn’t dependent on another. Tasks can run simultaneously.

Synchronous is a blocking architecture, so the execution of each operation depends on completing the one before it. Each task requires an answer before moving on to the next iteration.

Basically, Javascript is a single-threaded, blocking, sychronous scripting language used to make web pages interactive.
Being single-threaded and blocking means that javascript can only execute one task at a time i.e The program will execute the tasks in sequence, and each task must complete before the next task starts.

Although it’s synchronous by nature, JavaScript benefits from an asynchronous process. Long-running JavaScript functions can make the user interface (UI) or server unresponsive until the function has returned, resulting in a less-than-stellar user experience.
However, there are some instances where users can benefit from blocking programming, for example, when making an online payment.

The benefit of JavaScript is that it offers the best of both worlds: Single-thread and multi-thread, blocking and non-blocking. With this flexibility, programmers can write code in a single programming language instead of two—one for synchronous operations and another for asynchronous operations.

Asynchronous programming enhances the user experience by decreasing the lag time between when a function is called and when the value of that function is returned. Async programming translates to a faster, more seamless flow in the real world.
For example, users want their apps to run fast, but fetching data from an API takes time. In these cases, asynchronous programming helps the app screen load more quickly, improving the user experience.

Synchronous programming, on the other hand, is advantageous for developers. Synchronous programming is much easier to code. It’s well supported among all programming languages, and as the default programming method, developers don’t have to spend time learning something new that could open the door to bugs.

HOW TO CHOOSE BETWEEN ASYNCHRONOUS AND SYNCHRONOUS PROGRAMMING
When deciding which approach to take, consider asynchronous programming adaptable and synchronous programming strict.

Asynchronous programming is the multitasker, moving from one to-do to the other and alerting the system when each task is complete. Synchronous programming functions with a one-track mind, checking off one task at a time in a rigid sequence.

Asynchronous programming allows more things to be done simultaneously and is typically used to enhance the user experience by providing an effortless, quick-loading flow.
Synchronous programming is best utilized in reactive systems. While it is simpler for developers to code and is recognized by every programming language, sync is resource-intensive and can slow things down.

Below, i'll give some examples to better explain synchronous and asynchronous programming.
SYNCHRONOUS PROGRAMMING EXAMPLE

The output for the above code is;
Nissan 2003 true
{ Name: 'Nissan', Year: 2003, Good: true }
Adedamola 33 false
A man called god 300 true

In the above code snippet, all i did was to declare objects and assign values to keys.
you'll notice that the output given is in order with the code written above.. What this implies is that if there is an error with the first object being declared, the remaining code won't run because it's supposed to run synchronously.

ASYNCHRONOUS PROGRAMMING EXAMPLE

The output of the code is;
one
Three
Four
File appended successfully
A new file has been created
Two

This is an example of asynchronous programming because the tasks were not executed in order, and also one task did not wait for another to finish before executing.
Ideally, from the code written above, one should come before two and two should come before three and four. Also, a new file should have been created before the appending, but each task got executed based on the time it took for them to execute.
So it further solidifies the claim that asynchronous programming allows more things to be done simultaneously.

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