Rails的组成模块

查看系统裡面安装的gem包，可以发现如下的Rails相关的Gems。

actionmailer (1.3.2)    Service layer for easy email delivery and testing. actionpack (1.13.2)    Web-flow and rendering framework putting the VC in MVC. actionwebservice (1.2.2)    Web service support for Action Pack. activerecord (1.15.2)    Implements the ActiveRecord pattern for ORM. activesupport (1.4.1)    Support and utility classes used by the Rails framework. rails (1.2.2)    Web-application framework with template engine, control-flow layer,    and ORM.