The usefulness of HTML can be summed up in one quote, said by one of the most prolific programmers in modern history, Linus Torvalds. He created the most popular operating system that few people have heard of—Linux. As mobile phones surpass desktops, Windows is taking up a smaller and smaller percentage of hardware that is running it. However, when you take a look behind the scenes, Linux is the most popular operating system because every website, mobile app, or smart device that is connected to the Internet communicates to a Linux machine that is hosted in the Cloud at some point. Linus Torvalds had this to say about technology (emphasis my own):
I actually am not a huge fan of shiny new features. In processor design - as in so much of technology - what matters more is interoperability and compatibility. I realize that this makes people sad, because people are always chasing that cool new feature, but hey, in the end, technology is about doing useful things. And building and extending on top of existing knowledge and infrastructure is how 99% of all improvement gets done.
-Linux Torvalds (source)
This relates to HTML because it’s the foundational language of web browsers. To this day, the Web Browser is the only invention to be interoperable across all major hardware devices, including smartphones, desktop computers, tablets, and almost any piece of technology that has a screen. Moreover, the underlying programming languages that are used in web browsers are universal in their ability to create native experiences for these platforms. So, you can create mobile apps using the same set of languages used in web browsers: HTML, CSS, and JavaScript.
Interoperability - HTML is the Glue
HTML is a markup language, meaning it’s most useful for the actual written content in the web page. It does one thing really well: glue everything together. Whether you want to make an application or website, HTML will act as the glue that will make your work compatible across all hardware devices. Inside HTML, you can add links to style sheets that implement a design for your application and also to JavaScript files that add advanced level of interactivity and communication with the rest of The Internet.
This ability to interact and operate with several different physical (ex: camera, GPS) and digital (ex: Twitter, online translator) resources is what makes HTML the most interoperable language for most modern applications. This isn’t the only reason to learn HTML, though it’s the biggest one.
HTML is easy to learn
Most of knowing HTML is memorizing a small handful of tags that are similar to what one finds in a word document, with a few extra for supporting multimedia like images and video. Just knowing these basic tags and how to write them inside an HTML document is enough to support pretty advanced functionality like embedding YouTube videos, analyzing your website traffic, and a host of other useful things. It can be easy to get carried away just knowing basic HTML and creating your own personalized web pages. This experimentation and “play” is part of the fun of learning Web Development.
Like many other web technologies though, HTML is hard to master even if it is easy to learn. Especially, once you get into adding more advanced functionality through CSS and JavaScript, there are more things that you need to know to cross the chasm between a standard web page and a full fledged application or website that people will enjoy using. Regardless of the patience required to become an expert with HTML, it’s still worth learning.
HTML is here to stay
Although less than 30 years old at the time of this writing, HTML has become too crucial of a backbone to the free and open Internet. Anyone with a computer and a web browser can write HTML, it’s easy to learn, works across all devices with screens, and it’s been fine-tuned over many browser versions. This is no small feat because of the variety of web browsers that are currently available. All of the large technology companies have to agree on the set of standards that will be supported in their web browser from styling to interactivity. Often these standards are related to JavaScript, but HTML is still the glue that ties them all together.
After many decades of negotiation among these large technology companies, we have finally reached a fairly mature ecosystem that is well supported by the largest of tech companies in 2020, including Google, Facebook and Microsoft. All of these companies have hundreds of well-paid engineers who are the best in their field working on web technologies that can be freely used by anyone interested in making web applications like theirs. It is hard to imagine all of this effort being quickly discarded in short order.
Next Steps - HTML and the Document Object Model (DOM)
Now that you have the motivation to learn HTML, a good next step is to learn about how it works. Get started with some simple HTML code and a more thorough understanding about how HTML communicates with web browsers through its Document Object Model (DOM).