Every single application or website is a system (see the push in recent years for web assembly).
The difference is that a "systems programming language" has the capability of being used low level if needed while a "shit scripting language" such as javascript does not. Basically what I am saying here is that Javascript is an underwear taint-stain for modern computer science. With any luck it will be rid of this world in 20 years and you javascript programmers can stop torturing yourselves with new "hot libraries" and "ECMA transpilers" every 2-4 years.