What is JavaScript

JavaScript is a lightweight, interpreted or just-in-time compiled programming language with function priority; JavaScript is a dynamic scripting language based on prototype programming, multi-paradigm, and supports object-oriented, imperative and declarative style.

The operating environment of this article: Windows 7 system, Dell G3 computer, javascript version 1.8.5.

JavaScript is a programming language used to make web pages interactive. It gives life to the page - interactive elements and animations that the user engages with. If you've ever used a search box on a home page, checked out live baseball scores on a news site, or watched a video, there's a good chance it was made with JavaScript.

JavaScript and Java

JavaScript and Java are two different computer languages, both developed in 1995. Java is an object-oriented programming language. This means it can run independently in a machine environment. It is a reliable, versatile language used in Android applications, enterprise systems that move large amounts of data (especially in the financial industry), and embedded functionality for "Internet of Things" technologies (IoT).

JavaScript, on the other hand, is a text-based programming language designed to run as part of web-based applications. When first developed, it was intended to be a complement to Java. However, JavaScript has taken on a life of its own as one of the three pillars of web development - the other two being HTML and CSS. Unlike Java applications, which need to be compiled before running in a web-based environment, JavaScript is specifically designed to be integrated into HTML. All major web browsers support JavaScript, but most users have the option to disable it.

Using and Writing JavaScript

The beauty of JavaScript is that there is no need to know how to write it in order to use it in web code. You can find tons of pre-written JavaScripts online for free. To use this type of script, all you need to know is how to paste the provided code into the correct location on your web page.

Despite the easy access to pre-written scripts, many coders prefer to know how to write the scripts themselves. Because it is an interpreted language, no special programs are required to create usable code. A plain text editor like Notepad for Windows is all you need to write JavaScript. That said, Markdown Editor might make the process easier, especially when the lines of code add up.

HTML and JavaScript

HTML and JavaScript are complementary languages. HTML is a markup language used to define static web content. It provides the basic structure for web pages. JavaScript is a programming language used to perform dynamic tasks in this page, such as animations or search boxes.

JavaScript is designed to run within the HTML structure of a website and is often used multiple times. If you're writing code, it's easier to access your JavaScript if you put it in a separate file (using the .JS extension can help identify them). You can then link the JavaScript to the HTML by inserting tags. You can then add the same script to multiple pages by simply adding the appropriate tags in each page to set the link.

PHP vs. JavaScript

PHP is a server-side language designed to work with the web by facilitating the transfer of data from the server to the application and back again. Content management systems like Drupal or WordPress use PHP and allow users to write an article, which is then stored in a database and published online.

PHP is by far the most common server-side language used for web applications, although its future dominance may be challenged by Node.jp, a language that can be used in the backend like PHP A running but more simplified JavaScript version.

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