Is there any difference between global developmental delay and pervasive developmental disorders?

Developmental delays. There is a difference between the two. GDD is a delay in two or more of language, motor, vision, thinking and social skills. Pervasive developmental delays describe a group of disorders, such as Autism and Asperger's, that describe primarily delays of socialization, imagination, and communication.
Yes. Global developmental delays implies delays in speech, fine and gross motor skills. Pdd is thought to be part of the autism spectrum meaning that poor social interactions exceed other developmental delays.