The psychopath refuses to conform to social norms and obey the law. He or she often inflicts pain and damage on their victims, often with intentionality and still more often with a complete lack of understanding or care that their actions cause harm.
Consequently, psychopaths feel no remorse when they hurt or defraud others. They don't possess even the most rudimentary conscience. They rationalize their behavior and intellectualize it. A psychopath is never “wrong” because the psychopath’s own distorted view of reality does not allow for that possibility. They are master manipulators even to themselves, given their ability to engage in self-delusion.
Psychopaths fall prey to their own primitive defense mechanisms. The psychopath firmly believes that the world is a hostile, merciless place, prone to the survival of the fittest and that people are either "all good" or "all evil". Psychopaths are abusively exploitative and incapable of true love or intimacy. They are irresponsible, impulsive, irrational and unreliable. They do not honor contracts be they express or implied, any task they believe is not worth their attention, and any obligation that they perceive as a threat. They are unstable and unpredictable and rarely hold a job for long, repay their debts, or maintain long-term intimate relationships. In this manner they can be very dangerous, if only in terms of the emotional trauma they can cause for those unfortunate enough to have experienced a relationship of any kind with a true psychopath.
The terms sociopath, psychopath and ASPD are relatively interchangeable, at least from a clinical point of view. Any distinction is either semantic or aesthetic in nature, as all three terms describe the same basic personality type, one with a complete lack of conscience or the ability to feel remorse or even empathy. If you know someone who matches this description, it is best to keep your distance. Personality disorders, unlike mental illness, are considered a fixed construct. In other words, personality disorders are incurable. While it is possible for someone to modify elements of their own personality, the feature that makes it a disorder is that the afflicted person is usually completely unaware of their behaviors or the impact it has in those who love them.