In short your traditional playground bully has their own issues. They might bully you for two reasons. They have some sort of family issues and are looking for a release of all that built up anger or frustration and go looking for a punching bag which'll be a weaker or mainly different person, ie, someone who has better grades or is more popular, or just plain weaker. It's a jealous envy type thing. This isn't all bullies, but accounts for a large portion I'd bet.
Cyber I'd say are over rated. but in the case of cyber bullying and any bullying for that matter, it's all down to your confidence level. If you're very sure of yourself, you know what you're capable of, how smart you are and have common sense, you'll never have any trouble. Example, a cyber bully sends a death threat to you, you know they don't know where you live, or anything about you, they're just looking for a response. As you get older you realise not everything needs a response where as a younger person might take it more personally. It's all about the response.
If you show a weak response to any kind of bully when they taunt you, they're going to keep doing it. Believe it or not but words have power. but they are also a weakness if you don't use them properly. In regards to a playground bully, providing of course they're not too big of course, if you tell them to f- off, the chances are they won't, tell them again or you'll deck them, they're gonna test you.
Ok, fact is everyone is different, which means there's going to be a different way to deal with every a**hole you encounter in life. As you get older, wiser, you mature, there's less of them, but you will find them, that's how it goes unfortunately. But I assure you, the day you know what you're made of is the day you stop worrying about douchebags.
