No! Javascript the language and thread are not related.  If you find a Javascript implemented over JVM like ringojs uses JVM threads to execute JavaScript in parallel. In which case you get both event based within thread, and multi-threaded at the same time.<p><a href="http:&#x2F;&#x2F;ringojs.org&#x2F;documentation&#x2F;ringo_101&#x2F;" rel="nofollow">http:&#x2F;&#x2F;ringojs.org&#x2F;documentation&#x2F;ringo_101&#x2F;</a>