The Devil is in the details.
JavaScript (JS)
The JavaScript programming language was first developed in 1995 by Brendan Eich during his tenure as an engineer at Netscape. Originally intended to be called LiveScript, it underwent a name change before its release. Unlike many other programming languages, JavaScript (JS) does not inherently incorporate input and output functionalities. It is primarily designed to function as a scripting language within a host environment, with the responsibility of facilitating communication with the external world falling upon said environment. The most prevalent host environment for JavaScript is the web browser. JS, it is the most popular language used in web browsers worldwide. Although its name may suggest otherwise, JavaScript is not related to Java. It is an entirely separate language.
When it comes to running your JavaScript code, every web browser provides a built-in JavaScript Engine. One of the most popular ones is NodeJS, which allows you to execute JavaScript code outside the web browser environment.
JavaScript is considered an interpreted language, meaning that it is executed line by line without the need for compilation. This makes development and testing more efficient as you can instantly see the results of your code changes.
Additionally, JavaScript is dynamically typed, which means you don’t have to declare variable types explicitly. This flexibility allows for faster development and easier maintenance as you can modify variable types on the fly.
To ensure consistent behavior across different implementations of JavaScript, the language is standardized by the EcmaScript specifications. These specifications define the syntax, features, and behavior of JavaScript, ensuring compatibility and interoperability.
ECMAScript
European
Computer
Manufacturers
Association
(Standardized by ECMA International ECMA-262)
ECMAScript is a widely used scripting language that is primarily used for client-side web development. It was standardized by the European Computer Manufacturers Association (ECMA) and is now known as the ECMAScript specification.
ECMAScript, often abbreviated as ES, is the foundation for many popular programming languages, including JavaScript. It provides the fundamental syntax, types, and features necessary for building dynamic and interactive websites.
One of the key features of ECMAScript is its ability to manipulate the Document Object Model (DOM), which is a representation of the HTML structure of a web page. With ECMAScript, developers can dynamically modify the content, styles, and behavior of a web page in response to user interactions.
ECMAScript also includes various built-in objects and functions that extend the capabilities of the language. These include objects for manipulating arrays, dates, regular expressions, and more. Additionally, ECMAScript supports modern features such as arrow functions, template literals, async/await, and destructuring assignments.
With the continuous evolution of ECMAScript, new versions are released periodically, introducing additional features and improvements. It is essential for web developers to stay up to date with the latest specifications to take advantage of the newest capabilities and ensure compatibility with modern browsers.
In conclusion, ECMAScript is a powerful scripting language that forms the basis of JavaScript and enables developers to create dynamic and interactive web applications. Its versatility and constant evolution make it a crucial tool for building modern web experiences.
How to Insert a JavaScript File into an HTML Document?
JavaScript can be incorporated into an HTML file in two different ways:
- Internal JS: The JavaScript code can be directly added to the HTML file by encapsulating it within the
<script>tags. Depending on the specific requirement, the<script>tag can be placed either within the<head>or the<body>section of the HTML document. - External JS: Alternatively, JavaScript code can be written in a separate file with a
.jsextension. This external JavaScript file can then be linked to the HTML document by placing a<script>tag within the<head>section of the HTML file. Consequently, the JavaScript code contained in the external file will be inserted into the HTML page.
Linking an external JavaScript file offers advantages such as improved code organization and reusability.
