$ vim firstServer.js

输入：

var http = require('http');
http.createServer(function (request,response){
        response.writeHead(200,{'Content-Type':'text/plain'});
        response.end('Hello world\n');
}).listen(8888);

console.log('Server is running at http://localhost:8888/');

wq保存。

$ node firstNode.js 
Server is running at http://localhost:8888/

此时服务已经启动。

打开浏览器访问：

http://localhost:8888