Need permission for content hosted on a gaming website?

Hey guys I have been in an on/off process of deciding whether to go on and finalize my website in the gaming niche. I have always been in this niche as it is something I do enjoy writing about and doing, I was interested to know if I need special permissions to host or link to any gameplay, or pictures of video games. I know just about everyone is fine doing such things, especially gameplay hosted on youtube, but I was wondering if i would run into any trouble for not receiving permission or giving credit to each and every video and picture on the site. Any advice is welcome. Thanks again