I have to create a chat server page chat.html using node.js. I have used a a couple of modules like http://chat.nodejs.org. The problem is when I moved from chat.html page to some other page of my application like about.html and come back to chat.html I need to login again and it consider me a fresh joiner.
Is there any way/module using which I can persist the chat.
You'll want to set up sessions in your application. Rather than describe that here, I'll link this popular answer:
A simple approach would be to use sessions, to identify the user and load their chat history from a database.
You could also consider just storing their history into a cookie/localStorage and thus save some load on the server, unless you need to identify or store the history anyway.