Copyright on gaming & anime characters to use in my website

Pardon me. I'm new to this all.
I'd apprecitae answers focused primarily on this question.

I intend to build a website on gaming.
Now, I actually have intentions to put gaming characters and anime characters in the front page of my title. Is that legal?

I've seen hundreds of sites, using gaming characters ranging from Dead or Alive to Mario, and anime characters from different series being used in different indivudal websites. Is that legal? If so, is it something we can just do, or should permission be seeked before doing so?

I appreciate the answers and I apologies if this question it may not be clear to some. I don't even know if what I'm saying is correct in sense. I don;t even know if I'm in the right topic to put this up.

But I'm willing to learn as a side note apart from this question.

Many Thanks

--Antique--

As long as you are not using the actuall companys photos and your photo is unique to yourself you should be ok.