A lot of channels are freeon Roku including Youtube, Pandaro, Hasbro, Crackle, VEVO, Popcorn Flix, etc. But some channels are only for adult that is to be hide.

Where are these adult only channels on Roku? I haven't seen them.

under preferences you can isolate certain channels and it requires your personal code to turn them on. It is the Roku version of parental control. The channels WILL NOT be hidden.