Hey @YTCreators @TeamYouTube am I allowed to use someone else's YouTube content as ads for my products or services even if they are unaware of me doing so?
Your best resource will be the Copyright section of our Help Center, start with these top FAQs: https://goo.gl/FzBC2x . You can also review info on fair use, creative commons, and our troubleshooter linked from there. Hope these resources help answer your questions!