Actually, depends on the website.
This guy posted on a site which the parent co is Singapore govt
linked.
Also, those US commercial sites, like yahoo etc. When the local
police asks for info, they will release the IP address of the users
and more.
Anyone remember the 50 plus female doctor who was sent to jail
for tax evasion?
She deleted the patients bill data from the disk. In computer
speaks, the data, ie the 10101011 wasn't erased from the disk but
demagnetised. Only for an expert to remagnetised the disk and the
data will reemerged.
So be savvy when comes to using the net. Not everything is what
it seems and what it appears on the surface. Especially the young
kids - don't blindly follows or blindly mimics other.