JavaScript 101 /about js
We won’t cover much theory, so please don’t skip the small amount there is 😊
A tiny bit of history
JavaScript was introduced in 1997 to add interactivity to websites in Netscape Navigator 3.0 (the dominant browser at the time) but it was garbage. Despite that, everyone seemed to love said garbage. And so, to bring structure to the landfill, the ECMA (European Computer Manufacturers Association) began maintaining a standardized version called ECMAScript (ES).
In 2009, ES5 was released, introducing strict mode and improvements in reliability along with a few interesting new features still used today. Finally a real shift came with ES6 in 2015. It was a significant change from ES5 that web devs had been working with for years. It was a major update that introduced many new features and improvements to the JavaScript language, making it more powerful and easier to work with, after an initial period of adjustment.
We will be using many of these newer implementations in this course, such as classes, for...of loops, arrow functions, modules and mush mush more.
Since then, ECMAScript has been updated yearly (as of 2026 we're at ES2025), and JavaScript has grown into the most widely used programming language in the world.
JavaScript is one of the three core web technologies, alongside HTML and CSS. It allows developers to:
- create interactive user interfaces
- manipulate page content
- communicate with servers
- build full applications
It runs in all modern browsers and also on servers (via Node.js), which makes it useful for everything from small scripts to full applications. You can even create games and nativeNative: applications that run on a specific platform, like iOS, Android or Windows apps.
Course overview
This course focuses on building a strong foundation first. You’ll learn how JavaScript works and how to use it to control program behavior.
From there, we’ll move into increasingly practical tasks where you apply that knowledge to real problems and projects.
You’ll need to think logically and solve problems on your own. You will get better at this as we practice, since that's the only way to get good at it. I’ll guide you through the process, but the progress comes from doing the work. And I will be there to support you.
Remember: Programming is all about creating things, problem-solving
and maybe... we will also have some fun :)
Eventually we will create website implementations, native apps and even games. Exciting, isn't it?
Also, before we even start, let's get this between your ears: The console is your friend.
Programming uses language
Let's watch a short video about language...
As you might know, programming languages are written in English-like syntax to make them easier to read and understand. This is why we will use a lot of English in order to make the learning process smoother and more intuitive.
- Language is a means of communication. A tool.
- Languages are not always easy and logical. They evolve through use and history.
- Programming languages are also languages for communication. Only not with people but with computers.
Programming languages use English words because English has become the "standard" in the technology world. Nevertheless, they are harder to understand than English because they are more abstract.
Telling the computer what to do
Programming is the process of giving precise instructions to a computer to perform specific tasks. These instructions are written in a programming language, such as JavaScript, which the computer can understand and execute.
When you write code, you are essentially telling the computer what to do step by step. The computer follows these instructions in a specific order to achieve the desired outcome.
Some examples of instructions you might give a computer include:
- Performing calculations
- Displaying information on the screen
- Responding to user input
- Storing and retrieving data
To do any of these you need to learn a programming language, such as JavaScript.
Look! A wild programming language has appeared!
As mentioned earlier, a programming language allows you to interact with the web page and perform various tasks. Do know that a programming language is unlike English or Dutch. The computer does not think. The computer does exactly what you tell it to do.
You can't just say "Draw me a circle".
Which circle? Where?? Which colour??? How big????
The computer needs precise instructions
It may look like this:
Conclusion
Do know that everything matters. Every letter, parenthesis, semicolon (not so much in JS)
, capital letter, period and space. The computer blindly follows every instruction.