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Mahlil Mahee
Mahlil Mahee

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How Does JavaScript Work ???

In a short JavaScript work asynchronously with help of event loop in a single threaded environment to run non stop in the browser .

Now going To explain it more deeper .

Basically JavaScript run in the browser with the help of a interpreter which interprets each line of JavaScript code according to the given order and execute it in the browser .JavaScript is a high level , dynamic and interpreted programming language which is widely used for building web apps though it has a wide range of using field. JavaScript can interact with the DOM (document object model ) to dynamically modify the content , structure and styles of the page . When a user interact with the page , JavaScript respond to events such as clicking on a button and updating the DOM and executing code .The code is executed in JavaScript engine which are mostly in-build with the browsers, which parses and runs the code . JavaScript
can also make network requests to fetch data from a server allowing for dynamic and up to date information to be displayed on the page .

what is JavaScript event loop? want to here a story from me ?

Once upon a time, there was a busy little town called JavaScript Land. The town was always bustling with activity, as the inhabitants went about their daily tasks. One day, the mayor of JavaScript Land realized that the town was growing rapidly, and the number of tasks that needed to be completed was increasing every day.

To keep up with the demand, the mayor decided to create a new system for managing all the tasks in the town. He called it the "Event Loop." The Event Loop was designed to handle all the tasks that needed to be done in the town, one by one.

Each task in JavaScript Land was placed in a queue, and the Event Loop would work its way through the queue, completing each task in turn. When a task was completed, the Event Loop would move on to the next task in the queue.

At first, things ran smoothly in JavaScript Land. The Event Loop worked efficiently, and the inhabitants were happy with the new system. However, as time went by, more and more tasks were added to the queue.

The Event Loop started to get bogged down, and the townspeople grew frustrated. Some tasks were taking much longer to complete than they should have, and others were being pushed aside and forgotten.

The mayor of JavaScript Land realized that he needed to find a solution to the problem. He decided to prioritize certain tasks, so that the most important ones would be completed first. This way, the townspeople could get back to their daily tasks as quickly as possible.

And so, the Event Loop was improved, and JavaScript Land ran smoothly once again. The Event Loop continued to handle all the tasks in the town, one by one, making sure that the most important tasks were completed first. And the townspeople lived happily ever after.

So , did you understand the main theme of this story event loop is mechanism which helps JavaScript to interpret one piece of code at a time in an asynchronous way to run smoothly in the browser.

Now lets explain the asynchronous term here with a new story :::)))

Sure, let's consider a real-life scenario to understand asynchronous processing in JavaScript.

Imagine you're at a fast-food restaurant and you place an order for a burger and fries. You have to wait for your food to be prepared, but you don't want to stand around and do nothing while you wait. So, you decide to use the time to do something else, like browsing your phone or reading a book.

This is a classic example of asynchronous processing in real life. While you wait for your food to be prepared, you can do other things, and you'll be notified when your food is ready.

In the same way, asynchronous processing in JavaScript allows you to carry out long-running tasks in the background, without blocking the main thread of execution. So, your website or application can continue to respond to user interactions, even while a task is being processed in the background.

This makes your website or application more responsive and efficient, and your users won't have to wait for long-running tasks to complete before they can continue using your website or application.

That is all for today, you see how JavaScript had evolved to serve us more efficient and good user experience in this digital world as he knows time is valuable, so he saves a lot of time helping the website to be more efficient.

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