NODE.JS versus IIS (Why node)

Whats the point of node.js creating its own server and tries listening on it, isn't IIS/apache give us all of that? I understand its based on I/O Completion but we have web-servers technology in place. Can someone explain what can be achieved via node (apart from the java script on server side, which can be also achieved via SignalR) that can't be done via ASP.NEt and why we should focus so much on node when we have a tone of technology under asp.net stack Any classic example of node? typically for a enterprise dev. shop

Most web programming are for data display & eCommerce applications which are mostly database intensive, though lately it has been mash-up as well with web services, yes mobile web is a different game due to hardware sensors I agree but what is Node giving us which ASP.NET with SignalR can't give us?

TIA

What I find very interesting with Node is that everything is event based, which is different than programming ASP.NET or PHP where behavior is more sequential. Not a bad thing, just a different way of doing things.

You can program the server itself (as opposed to programming applications that run on the server) to do more than serving files, the typical example with Node is the chat room application where you broadcast messages to all participants and each can send messages to the server. By programming your own server events (like listen, error, connect etc) you have a lot of control over how things go server side.

Then of course npm, the node package manager, is definitely a plus over having to manually work the dependencies if you want to use 3rd party libs.

To host an ASP.NET site/app you need IIS which is a proprietary system, whereas Apache and Node are more open. Granted though, Node hosting is not as widespread as Apache based hosting.

Hope this answers some of your questions

Each technology can achieve anything. If you prefer ASP.NET over Node, use it. ASP.NET is extremely powerful and there is no reason to use Node over ASP.NET when you have the expertise and software/money to run your services. Node is just different; it has a different execution model (no threading whatsoever) and above all, it is open source and free. It is easy to get started on any OS, and easy to deploy on any OS. But in the end, it comes down to; what do you prefer?