text: var http = require('http');
  
  var server = http.createServer()
  
  server.on('request',function(req,res){
      //plain 為普通文本, css 為樣式類型, html 為 html code 類型
      res.setHeader('Content-Type','text/plain; charset=utf-8')
      res.end('test 哈哈哈哈哈')
  })
  
  server.listen(3000,function(){
      console.log('server is running')
  })