Vladimir Propp analyzed Russian folk tales and identified 31 narrative functions or events that consistently occurred across stories in a fixed sequence. Some examples of the narrative functions included a family member leaving home, an interdiction being given, the interdiction being ignored, a villain appearing, harm being caused, a lack or need being identified, a decision to counteract being made, and the villain being defeated. Propp also categorized the common character types found in these folk tales, such as the villain, donor, helper, princess, dispatcher, and hero.