When you meet someone who has Asperger's syndrome, you might notice two things right off. He's just as smart as other folks, but he has more trouble with social skills. He also tends to have an obsessive focus on one topic or perform the same behaviors again and again.
Doctors used to think of Asperger's as a separate condition. But in 2013, the newest edition of the standard book that mental health experts use, called The Diagnostic and Statistical Manual of Mental Disorders (DSM-5), changed how it's classified.
Today, Asperger's syndrome is technically no longer a diagnosis on it's own. It is now part of a broader category called autism spectrum disorder (ASD). This group of related mental health issues shares some symptoms. Even so, lots of people still use the term Asperger's.