Getting Started With Javascript


javascript is a client-side scripting language that runs in web browsers. It is very popular and used by a lot of people in many different ways. There are other languages that can run in web browsers, but javascript is the most popular and has special features to deal with the environment of a web browser.

JS allows developers to add interactive elements to web pages, such as pop-up windows, search bars, audio and video, chat widgets, and more. It also lets developers provide real-time updates to a page without reloading it. For example, news tickers and stock or crypto prices often use JS to display live data on the page without having to reload it each time they update. JS is also the foundation of most in-browser games and applications, which allow users to interact with characters and interfaces through their browsers.

There are a few things you need to know before you get started with javascript. First, you need a modern web browser that supports it. Firefox, Chrome, Safari, and Microsoft Edge all support javascript. Next, you need to know how to use the JavaScript console, which is a built-in tool that enables you to enter javascript and have it executed on the current page. To open the console, press Control+Shift+J (Windows) or Command+Option+J (Mac). Once you’ve opened the console, you can start typing javascript into it. The console will evaluate your code as you type it and show you the result on the screen, so you can see what happens when you execute the snippet. If you miss a punctuation mark or accidentally enter a space, the console will still show you the result and let you continue typing.

One of the key features in javascript is the concept of scope. This refers to the position of a piece of code in your script and what other parts of your script can and cannot access it. This is achieved through the creation of an Execution Context, which acts as a sort of sandbox for your functions and variables.

As you write your code, the javascript engine will process it and update the Execution Context. Once the EC has all the necessary information, it will transform it into executable byte code and execute it. This process is known as inlining. Inlining is an optimization technique that reduces function calls and improves performance.

Another important aspect of javascript is its object-oriented design. JS provides a variety of object-oriented programming features, such as inheritance, encapsulation, and polymorphism. Using these techniques allows you to create more complex applications with fewer lines of code. This helps to ensure that your code is maintainable and easy to read, and it will be a lot easier to debug if you need to. It is also more secure and prevents unintended behavior by other programs running on the same server as your javascript. In addition, it provides a standard library of functions that can be used to help with common tasks such as string manipulation, arithmetic, math, and calendar functions.