In the short chapter, What is Node by McLaughlin, he writes:
"Node has no blocks, no threads competing for the same resource (Node is happy to just let things happen however they happen), nothing that has to start up upon request. Node just sits around waiting (quite literally; unused Node responders are sleeping). When a request comes in, it’s handled. This results in very fast code, without uber- programmers writing the server-side behavior."
While I think he's picking on PHP here - from what I understand there isn't a way for PHP to not call up new references to its databases, files, etc, whenever any php page is loaded - is this really different than other web technologies? Consider Django/Flask for example or a simple Python threaded-server using builtin methods - is it really any different than the no-blocks advantages of Node? You run a program and it binds a socket, running the function only as needed. (Doesn't Java also do this?)