The Javascript standard is extensive — more than 1,100 printed pages — so it is far beyond the scope of this article to provide basic information on every Javascript (JS) characteristic and feature. Instead, this article will introduce you to the characteristics of Javascript that make it such a popular language while mentioning a few caveats to remember when using Javascript in your own projects.

What are the Main Characteristics of Javascript?

Speed

Javascript (JS) is built for speed because its primary purpose is to handle dynamic content. Dynamic content is the part of a website that changes when you click on a button or a specific region of the page, like a dropdown menu.

Picture flipbooks, videos, file sharing, and many other things we take for granted on the web wouldn’t be useful if they couldn’t function fast enough. We wouldn’t want to take 5 minutes to flip a page in an online book, for example.

The Javascript community is always working to make the language faster, and modern Javascript can do more complex tasks more quickly than previous versions. For example, asynchronous loading is much faster in modern browsers than it once was.

Versatility

Javascript has expanded its role in web development thanks to teams of developers across the world who have reimagined what the language can do. It’s still an important part of client-side user experiences with dynamic content, but server-side Javascript has given the language new life and utility in the days of increasingly complex development stacks.

Web developers can now program front- and back-end code with Javascript. Javascript has expanded so that it can handle dynamic content on your web browser, generate web pages on a server, and connect to databases.

Javascript also offers multiple styles of programming which developers can tune to their preferences. Developers who prefer functional programming can put their focus on reusable functions, while those who prefer object-oriented programming can create objects with persistent states and behaviors.

Extensibility

The official Javascript standard only tells part of the story when it comes to the ways Javascript is used in the real world. Companies that create web browsers, such as Google, Microsoft, and Mozilla, often add features to their proprietary Javascript implementations that run on their browsers.

Many features that today’s Javascript developers rely on, like the dynamic selection of HTML nodes and the first implementations of Javascript classes, came from features dreamed up by private developers. These features eventually made their way into the official Javascript standard, paving the way for more innovations to come.

Javascript frameworks also are a major source of new Javascript abilities, since they allow developers to create complex actions more easily than vanilla Javascript. For example, although it can be done in vanilla Javascript, developers almost always prefer to use a framework like JQuery for asynchronous function calls.

What are the Caveats of Javascript?

Popularity

The overwhelming popularity of Javascript (JS) means that it’s almost impossible to become a full-stack web developer without knowing at least some of the language. Javascript also has a tougher learning curve than it once did, because learning Javascript also often means learning one or more of its frameworks as well.

New Javascript frameworks are also popping up frequently, so it can be difficult to find time to learn the newest popular framework. Even though skills from one framework can translate into working with other frameworks, misconceptions that the newest frameworks are the “best” are common, and skills with older frameworks can fall out of favor.

Fortunately, knowledge of vanilla Javascript and its basics will always have a place in web development, since there are some instances where frameworks aren’t necessary. You would never use a framework to print information to the console, for example.

Usability

The vast majority of websites rely on Javascript, whether they are dynamic or not. Since server-side Javascript has become so popular, generating websites using Javascript has become far more common.

All web pages which implement functionality through Javascript have one vulnerability: that small segment of the browsing population who choose to disable Javascript. Failing to write code to provide alternative functionality risks missing out on some important visitors.

Javascript can also cause accessibility problems for people with disabilities if it’s not implemented well. People who use screen readers have a notoriously difficult time handling dynamic content, so Javascript developers should always be aware of the extra work required to design in a universal way.

If you are interested in learning more about Javascript (JS), Udacity has many other articles about this popular programming language. All you have to do is look through our blog.

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