Three simple things
1. A robot may not injure a human being or, through inaction, allow a human being to come to harm.
2. A robot must obey orders given it by human beings except where such orders would conflict with the First Law.
3. A robot must protect its own existence as long as such protection does not conflict with the First or Second Law.
Isaac Asimov's "Three Laws of Robotics"
I can never remember the 3 laws, not that it's pivotal information to have at a moments notice, but still.