I see many people are confused about Schizoid and Aspergers.
So, I'm gonna to add some difference from the link:
asperger-syndrome/topic36592.html
What is the difference between Schizoid Personality Disorder and Asperger's Syndrome?
There are some core differences between AS and SPD, the biggest one being that AS is a form of autism while SPD isn't. We could say that AS is a person with a differently wired brain, but that a person with SPD has a "neurotypical" brain that just happened to develop a peculiar personality of extreme introversion and emotional detachment.
People with SPD don't have many of the "autistic" characteristics of AS, like the strong preference for logical patterns in things and people, a natural interest for numbers and other logic related things, the inability to read facial expressions and the lack of innate knowledge that other people aren't rule based and have motivations that might be different than the person with AS.
SPD is more about never-ending introspection, rationalisation and hyperreflection about pretty much everything. People with SPD have an extremely rich internal world that only rarely surface, and from the outside, people with SPD seem to be completely aloof and detached; but they are in no way autistic. It's just that they rationnalise and internalise everything, but their understanding of the world around them is completely unaffected. They can participate in discussions normally, can get along with people like anybody, but are very unlikely to participate in them by themselves if they don't have to and will almost always prefer to be alone. They do have a strong tendency to be perpetually daydreaming if left idle and are likely to think about fantasy and fictious worlds much more than "normal" people would.
People with SPD may be socially inept due to lack of practice and lack of motivation. They are withdrawn because it makes life easier, because they do not gain a great deal of happiness from getting close to people.
People with AS have an inability to understand social cues. I would say they are withdrawn when they are engrossed in their particular fascination.
People with Schizoid personality disorder are not diagnosed and treated because, they are unlikely to seek medical help and if they do so that doctor or psychiatrist will find it difficult to see how the patient can be helped.
Mostly though people who suffer from Asperger are mentally unable to read the emotional states of other people, while people who suffer from Schizoid Personality Disorder can have an excellent understanding of other people's emotions but don't care about them or don't seem them as being relevant.
People with Asperger's have developmental problems, and it poses a lot of social issues, such as inability to pick up on social cues. It's basically a mild form of autism. They usually have limited interests, and like having constant routines that they follow.
Hope this will help some people realize wheather they have AS or SPD.
Hope it'll help.