Javascript runtime environments
From wikinotes
Javascript is executed by a javascript engine (ex: v8).
the runtime environment is how you communicate with it.
Generally, this environment is provided by your web browser.
There are also tools like node.js that let you run javascript on the commandline.
Runtime Environments
nodejs interpreter, cli spidermonkey (firefox) includes interpreter, cli
Engines
v8 google chrome's javascript engine spidermonkey firefox javascript engine nitro safari javascript engine