I got this. A Sociopath is someone who is in it for themselves, meaning everything they do is for their benefit. They will lie, cheat, steal, and sometimes kill (the latter is VERY rare, the ones you do hear about are just reported stories), to get what they want. Early onset Sociopaths (meaning they developed it early on) will usually see improvement on the disorder in their late teens/early adulthood. Some will have it all throughout life. They are typically not physically dangerous, and you won't really meet one unless you know them. They are great at hiding it from others, and usually it is the family/close friends that see the disorder in action.
Sources: Many years of research on disorders/sister is a sociopath.
A sociopath is a person who gets enjoyment out of hurting or killing another living things. Most sociopaths start out by torturing or killing small animals like mice or squirrels and may move up to larger animals such as cats an dogs. Some sociopaths eventually go unnoticed and untreated for so long that they upgrade to torturing and killing humans. This is where we get most serial killers today.