t1 = Thread.new { loop {} } t2 = Thread.new { sleep 5 } t3 = Thread.new { Thread.stop } t4 = Thread.new { Thread.exit } t5 = Thread.new { raise "exception" } puts s1 = t1.status # "run" puts s2 = t2.status # "sleep" puts s3 = t3.status # "sleep" puts s4 = t4.status # false puts s5 = t5.status # nil