Node.js 是构建于Chrome的JavaScript引擎的，Google的浏览器Chrome，有一个很是快速的JavaScript引擎，叫做V8。那个JS引擎可以被自力出来。Node.js就是建树在V8之上的。这也是为什么Node.js会运行的如此之快。关于开发者来说，有几个好处：
你不須要從頭進修一門新的說話，它就是JS。我經常查看Chrome和Mozilla的JS文檔，他們完全通用。

Node.js 安装

1、安装编译环境，>sudo apt-get install g++ c++ curl libssl-dev apache2-utils git-core curl
2、下载Node安装包，>wget http://nodejs.org/dist/node-v0.3.0.tar.gz
3、編譯安裝，步驟如下：
>./configure        //注：如果不需SSL，可进入选项-without-ssl
>make
>make install
4、安裝成功，默認路徑爲：/usr/local/bin/node！

Node.js 应用

1、安装成功后先写“Hello World!”简单测试一下，代码如下：
Java代码  
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//filename: app.js    
var http = require('http');    
http.createServer(function (req, res) {    
 res.writeHead(200, {'Content-Type': 'text/plain'});    
 res.end('Hello World\n');    
}).listen(8000, "127.0.0.1");    
console.log('Server running at http://127.0.0.1:8000/');
2、运行 app.js，>node app.js，在浏览器输入http://127.0.0.1:8000/，即可看到结果
3、Node提供了一些常用的API，可參考：http://nodejs.org/api.html

NPM 安装

除Node自己提供的API外，現在有很多第三方模塊可極大的提高開發功效，如：WEB框架-express，HTTP中間件-connect，模板-ejs等，爲了管理這些模塊我們在线需要安裝NPM，安裝過程如下：
1、第一打算目录权限，不要以ROOT帐号安装，>sudo chown -R $USER /usr/local
  fedora下，先用root更改权限 chown -R $USER /usr/local 之后退出root
2、安装NPM，>curl http://npmjs.org/install.sh | sh
3、完成后安装第三方模块也很简单，>npm install modules_name，安装Express，>npm install express
注：如果安装模块的过程中报域名毛病的话，请清空缓存 >npm cache clean 或重启计算机即可

值得關注的更新：

Build

FreeBSD 10 is no longer supported. #22617

child_process

The default value of the windowsHide option has been changed to true. #21316

console

console.countReset() will emit a warning if the timer being reset does not exist. #21649

console.time() will no longer reset a timer if it already exists. #20442

Dependencies

V8 has been updated to 7.0. #22754

fs

The fs.read() method now requires a callback. #22146

The previously deprecated fs.SyncWriteStream utility has been removed.#20735

http

The http, https, and tls modules now use the WHATWG URL parser by default. #20270

General

Use of process.binding() has been deprecated. Userland code using process.binding() should re-evaluate that use and begin migrating. If there are no supported API alternatives, please open an issue in the Node.js GitHub repository so that a suitable alternative may be discussed.

An experimental implementation of queueMicrotask() has been added. #22951

Internal

Windows performance-counter support has been removed. #22485

The --expose-http2 command-line option has been removed. #20887

Timers

Interval timers will be rescheduled even if previous interval threw an error. #20002

nextTick queue will be run after each immediate and timer. #22842

util

The WHATWG TextEncoder and TextDecoder are now globals. #22281

util.inspect() output size is limited to 128 MB by default. #22756

A runtime warning will be emitted when NODE_DEBUG is set for either http or http2. #21914