Simula is a name for two programming languages, Simula I and Simula 67, developed in the 1960s at the Norwegian Computing Center in Oslo, by Ole-Johan Dahl and Kristen Nygaard. Syntactically, it is a fairly faithful superset of Algol 60. Simula 67 introduced objects, classes, subclasses, virtual methods, coroutines, discrete event simulation, and features garbage collection.