Please explain what are the differences between autism and asperger's?

Asperger's Syndrome: ...Is the old term for "mild" or "high functioning" autism.

The same deficits : in reciprocal social interaction caused by lack of joint attention, facial recognition & theory of mind underlie all types of autism. Autistic Spectrum Disorder is now the diagnosis that "lumps" autism, AS & PDD-NOS in the DSM-V. There was a misperception that the old diagnosis of AS always implied superior cognitive skills. The DSM-IV required a "normal" IQ (> 70), not necessarily avg. or >.