Imitation refers to the emission of a behavior that is topographically similar and temporally proximal to the behavior of a model. In other words, Imitation means "to mimic another person's behavior". Infants and children absorb vast amount of information through the imitation of others. Imitative learning allows children to observe, then practice and rehearse the behaviors they've seen. This leads to the mastery of countless new sills.
Once a generalized imitation repetoire is established, the learner has acquired a response class as "doing as the model does". These imitation skills play a powerful role in behavioral development of children. The emergence of language, social, daily living, and play skills are often products of generalized imitation.
Most children with Autism Spectrum Disorders have what has been called a "core deficit" in the ability to imitate. They often show little interest in the behaviors of those around them and do not often attempt to imitate what they see. Poor imitation skills indicate that the child with ASD is not observing and learning from the world around them. Failure to imitate means that new skills are not practiced or mastered.