The distinctions which I vaguely remember from over 40 years ago are not followed today, and has been pointed out by several persons (including myself) are embodied in the antisocial personality disorder.
“Insane” is too vague a term. What do you mean by this? Do you mean a psychotic? One who has a psychosis has lost contact with reality, either through hallucinations or delusions. These people are not psychotic since they are in contact with reality. They have a mental disorder, antisocial personality disorder, which is almost just like other mental disorders, such as depression. The difference is that there is no known cure.
It is possible that such a person has lost contact with reality, but if that be the case, another diagnosis would be called for, such as schizophrenia. BTW, schizophrenia is also not curable.
Closely related to the antisocial personality disorder is “borderline personality disorder.” You can look that up in the cite furnished by Mirage. The basic difference is that an antisocial personality d/o person may harm you, but a borderline personality d/o may harm himself.