but why this is happening? why people have that trait of behaving like this when they are confident about anonymity? probably it's consequence of problems in teenage-hood, or something. and adding to this topic, i'm also curious about reasons why people are 'trolling', especially when their 'trolling' is offensive, angry. and i have no clue what causes that behavior..
Is it anonymity, or is it the venue? As I type this I do not particularly feel like I am talking directly to you, rather leaving a mark for future readers to stumble upon, so to speak, under the context you have set.
I am thinking about what other people would want to read, not how you personally might feel about what I say. I expect that leads to things said that would not be said if I were speaking directly to you, such as in an email, for instance.
I don't know if that fully explains offensive and angry posts, but that could simply be a matter of someone having a bad day and wanting the world to know it.
Actually, the bit about being a jerk behind anonymity isn't particular to nerds: studies show it cutting across pretty much all walks of life. That doesn't excuse the nerds, but it does mean that examining the problem in the context of nerds alone probably isn't very useful. Nobody is immune, and as it turns out, nerds are not especially susceptible. Whatever causes this, it speaks to something much more universal than nerddom.
In a way I suppose because it's easy. A lot of people are unsure of themselves and feel better after they tell someone else just how dumb he is. The thought is: "Gee, I 'm not so dumb, just look at that guy!" Most designers I know tend to be unsure deep inside. Nerds? Could be just the same.