Hi, I was wathcing this video on YouTube about differences between javascript and php and I found that Javscript is not free and php is open source, but i didn’t understand, I can use Javascript free so what it means?
Thank you!
That video is not correct. JS is an open standard. Anybody can implement a javascript engine because all of the requirments and standards are freely available. Can someone implement a JS engine and then charge for it? Sure, why not. But when was the last time you had to pay to use a web browser with JS in it 
You do not have to pay to use JavaScript. Unlike some languages, the public cannot make direct contributions to changing the implementation of the language. Technically “JavaScript” is a trademarked name owned by Oracle. It is the most common/popular implementation of the ECMAScript language standard which is controlled by ECMA International. In order to propose changes to the standard, you have to be a member of the 39nth Technical Committee or a recognized contributor.
But, as @bbsmooth pointed out anyone is welcome to build their own implementation of the standard.
thanks now is clearer!
yes, javascript is open source programming langulage