Good practices

Code you JavaScript code in a separated file (ex. script.js)

Include the code in your HTML file using defer

<script src="script.js" defer=""></script>

(+) Separation of concerns: HTML=document structure; JS=logic
(+) defer keyword: non blocking JS loading. Execution while HTML DOM is loaded.

Avoid inline JS within HTML file

<!-- Avoid -->
<script>Some inline JS code here</script>

Use the current standard

Language specification standardized by ECMAScript.
Conform to the current ECMAScript v6.
\(\Rightarrow\) Add in the first line of your script

"use strict;"

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