Rails Symbols
It is very important to understand symbols and how it behaves in Rails. Symbols concept was very confusing for me before. Again, Google to the rescue! 
I found a good article from Gluttonous that explains how symbols work.
As I progress through Agile Web Development with Rails, I notice that symbols and strings can be used interchangeably in most cases. For example:
redirect_to(:action => “index”)
redirect_to(:action => :index)