I'm surprised to find that no one has yet bothered to inquire after the problem of evil, and how my world view addresses this topic!
Well, for me, that's pretty much an open-ended discussion, but I gravitate towards a view that perceives evil as an error of perspective, both on the part of the perpetrator and on the part of the suffering party. If ants were self-aware individuals capable of verbalization, they'd probably conceive of an exterminator as a supremely evil being who threatens their very survival - yet from a human perspective, he's a guy doing his job so that our kitchen supplies are no longer infested with bugs.
"Evil" is not necessarily a meaningless or arbitrary term, as some would suggest, but its usefulness is somewhat limited; in fact, it can even be downright counterproductive when people end up conceiving of the Other Party as evil, and end up committing atrocities in the name of "Good".
In short: "evil" pertains to the social systems our species has created upon a foundation of very old behavioural patterns we share with many other organisms that live in a group setting. These patterns aren't random, but directly related to the functionality of a given group.