There are area of space with higher security. If they attack you, they ARE gonna get raped. There are people who suicide gank tho. It's rare and have never been suicide ganked, it mostly happen if you are hauling an important cargo. The fact that you can be attacked anywhere (especially in lowsec space, where the most profit, and the most fun can be had) just makes alliances/corps really important. Honestly, the PvP is the main reason why I started playing, I wanted a good sandbox game with a good PvP system, and EvE has it. In a few months when I get better I'll probably join a Pirate corp or a territorial warfare corp/alliance.
http://www.youtube.com/watch?v=08hmqyejCYU
(ofc take everything with a grain of salt)