signature link is Spammer?????????

[michealjohn40]

Hi
everyone
I am new on this forum and find the alot of nice things. I want to make good frieds here.
My first question is that If you use put link in signature then its spam or not?
if it is not spammer then why forum owner remove post or banned the user???
If it called spammer then why forum owners give this option.
Its the main issue i feel please share your views.
waiting to your response.
thanks