JavaScript has a rich grammar and syntax, developed over years of use and refinement. Using ES6, we have a whole host of data types, methods of declaring functions, and code standards. While writing JavaScript can seem to be playing very loose and fast, there are best practices, and the fundamentals of the language are as robust as other languages. Remember that capitalization counts; don't use reserved words for variable names; use const or let to declare your variables; even though JavaScript is loosely typed, data types are important; and conditionals, loops, and functions all help structure the logic of your code.
A mastery of the grammar and syntax of JavaScript is vital to understanding how to use this robust language, so take your time familiarizing yourself with the details and intricacies. Moving forward, we will presume you have fluency in JavaScript's style as we get into more difficult material.
In the next chapter, we will get our hands dirty with data and...