Ramaze : index. Ruby Fibers: 8 Useful Reads On Ruby’s New Concurrency Feature. New to Ruby 1.9 is the concept of fibers.
Fibers are light-weight (green) threads with manual, cooperative scheduling, rather than the preemptive scheduling of Ruby 1.8's threads. Since Ruby 1.9's threads exist at the system level, fibers are, in a way, Ruby 1.9's answer to Ruby 1.8's green threads, but lacking the pre-emptive scheduling. Now that Ruby 1.9 is becoming more important with each passing month, I've rounded up some of the best articles about Ruby 1.9's fiber functionality so that you can be up to speed with all of the major concepts in perhaps 10 to 15 minutes.
If you're getting interested in Ruby 1.9, you'll want to read on: Fibers & Cooperative Scheduling in Ruby - Ilya Grigorik hits it out of the ballpark with perhaps the best overview of fibers.