On Thu, May 24, 2007 at 12:29:58AM +0900, Dennis Crissman wrote: > I am confused, can somebody please explain to me the difference between > these two calls? > > I tried some variations below, and the only one that worked was the > obsolete require_gem call. > require 'active_record' The developers of ActiveRecord made the (IMO unfortunate) choice of having the name of the file (active_record.rb) be different from the name of the gem (activerecord).