A term used to describe external JavaScript files used in a project.
"External JS" is a term used to describe external JavaScript files used within a project.
These files have the extension .js and contain solely JavaScript code that is to be called from HTML or other JavaScript programs.
In contrast, internal JS would include in-tag event-handlers for HTML and code that is written between <script> tags on a single page.
Important Links
Official JavaScript Specification: http://www.ecma-international.org/ecma-262/7.0/index.html
Official Document Object Model (DOM) Standard: https://www.w3.org/standards/techs/dom#w3c_all
Official HTML Standard: https://www.w3.org/standards/webdesign/htmlcss