HelloWorld

const http = require('http');

const port = 3000;

http.createServer(function (request, response) {

    // 发送 HTTP 头部 
    // HTTP 状态值: 200 : OK
    // 内容类型: text/plain
    response.writeHead(200, {'Content-Type': 'text/plain'});

    // 发送响应数据 "Hello World"
    response.end('Hello World\n');
}).listen(port);

// 终端打印如下信息
console.log(`Server running at http://127.0.0.1:${port}/`);