primitive. javascript example - in Visual Studio Code

java script is single thread , where u can create once , but if you wanna use multiple can be two thread using 3 ways . call back function , promises all and async wait .
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how to create javascript in html
always write java script within body but end of the html condition using
tag ...
//
//html>....

//or
use external link . just like stylesheet . creatiing file name name.js ...
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