The Internet is all about freedom of information. Its space that doesn't exist. concepts , Images and Activity is thrown around at light speed via cables, Much like in you head. The internet is the collective brain of society (we are the most evolved ants ever), YOU are a sub set.
The following links discribed by there names are all dangerous
(espeacially if you fear the unkown in your head <ignorance> and fear reverse psycology)