The word autism was first used in the English language by Swiss psychiatrist Eugene Bleuler in a 1912 number of the American Journal of Insanity.
However, the classification of autism did not occur until the middle of the twentieth century, when in 1943 psychiatrist Dr. Leo Kanner of the Johns Hopkins Hospital in Baltimore reported on 11 child patients with striking behavioral similarities, and introduced the label early infantile autism. He suggested "autism" from the Greek autos, meaning "self", to describe the fact that the children seemed to lack interest in other people. Although Kanner's first paper on the subject was published in a (now defunct) journal, The Nervous Child, almost every characteristic he originally described is still regarded as typical of the autistic spectrum of disorders.
At the same time an Austrian scientist, Dr. Hans Asperger, described a different form of autism that became known as Asperger's syndrome—but the widespread recognition of Asperger's work was delayed by World War II in Germany, and by the fact that his seminal paper wasn't translated into English for almost 50 years. The majority of his work wasn't widely read until 1997.
Thus these two conditions were described and are today listed in the Diagnostic and Statistical Manual of Mental Disorders DSM-IV-TR (fourth edition, text revision 1) as two of the five pervasive developmental disorders (PDD), more often referred to today as autism spectrum disorders (ASD). All of these conditions are characterized by varying degrees of difference in communication skills, social interactions, and restricted, repetitive and stereotyped patterns of behavior.
Few clinicians today solely use the DSM-IV criteria for determining a diagnosis of autism, which are based on the absence or delay of certain developmental milestones. Many clinicians instead use an alternate means (or a combination thereof) to more accurately determine a diagnosis.