Recently,I'm studying ruby

Recently,I'm study ruby and reading a book named <Ruby Hacking Guide> which was translate to Chinese and I download from this link(Ruby Hacking Guide中文版第一部分发布了！).When I read this book,I know many knowledge about C and OO and how the ruby define a class and explain it and execute.
1.how to define and call a point of function in a structure.
2.define a register var.
3.know how the hash map work.
4.know why there need be a hash function in a class.

Although I know many thing about how ruby be explained and executed,I didn't know how to use ruby to develop a simple program.I will study the ruby knowledge such as how to define a class,how to define an object and the libs of  ruby and so on.Later,I may  study  the rails  a  framework of ruby.

A few days ago,I had seen the new features of the Ext 2.0.There is a very beautiful function in its demo that it can build a Windows Desktop in browser.So I want to develop an application about this with ruby on rails.But I don't know when I can begin.