Jan 23, 2019

How to Write JavaScript: The Basics

JavaScript is an essential component of intelligent website design, providing the tools for creating interactive features that enhance the end-user's enjoyment. If you're thinking of taking a JavaScript certification exam, it's possible to start teaching yourself some of the core principles. This kind of self-learning gives you the opportunity to develop your first few web-based applications before signing up for an Intro to Programming course or JavaScript course to take your knowledge to the next level.

What Is JavaScript?

HTML forms the basis of any website, telling the site how to display text and images and how to navigate between pages. However, Internet users demand much more from their online experiences and expect websites to be interactive and personalized. That's where the programming language JavaScript comes in. It provides a layer of intelligence for informing the website how to react to commands, update information from a web server, change content, and generally provide a more engaging experience.

JavaScript is incredibly versatile. For example, in addition to building websites and website applications, developers use it to create web-based presentations for meetings or server applications. It's a particularly powerful tool for mobile developers creating apps for handheld devices.

What Do You Need to Write JavaScript?

JavaScript is very accessible. If you have a computer, you already have everything you need to get started:

  • A web browser: For translating, displaying, and testing your JavaScript
  • A text editor: For writing your JavaScript

Adding JavaScript to a Website

JavaScript is a powerful and complex scripting programming language, with many concepts to learn; but it's actually quite simple to write your first JavaScript application to demonstrate some of the possibilities. To get started, open an HTML file in a text editor. The file has a series of tags that tells a web browser how to interpret the contents, and these tags are always in pairs. For example, the tags < html > and < /html > designate the beginning and end of the HTML code and let the browser know that anything within those tags is HTML. To add your JavaScript, you need to let the browser know it must interpret your code as JavaScript rather than HTML, so you use the < script > and < /script > tags. JavaScript goes between the < body > and < /body > tags or the < head> and < /head > tags.

As a simple example, it's possible to create a ""Hello World!"" application by placing the following line of code between script tags in the head section of a HTML file:

alert('Hello World!');

When you save the file and open it in a web browser, a JavaScript alert box pops up displaying the welcoming phrase.

JavaScript Certification Exams

JavaScript is easy to get into, and by referring to a few online resources it's possible to start learning the basics; but getting your foot in the door as a JavaScript programmer requires the best JavaScript certification. A Udacity Nanodegree program offers JavaScript certification online, providing the fundamental knowledge to advance your career in web development.