this might be easier to understand for step 0.

demo.js

// An attempt to simplify the basic node starter script.
// USAGE: node demo.js

var http = require('http');

function listener(request, response) {
	console.log('URI: ' + request.url);
	response.writeHead(200, {'Content-Type': 'text/plain'});
	response.end('Hello, World\n');
}

http.createServer(listener).listen(1337, 'localhost');
console.log('Server running at http://localhost:1337');

request.url is the "script_name" or "uri" ... imho ... could not saying "URI" simplify?