Questions about dtube

Hey,I am new to steemit and dtube and I was wondering if anybody could answer some questions for me.
1)If dtube is decentralized where are all the videos stored?Are there any limitation to what you can upload?(like size/duration/how often you upload etc?)
2)The thing that gets me hyped for dtube is the lack of censorship ,but how far does that go exactly?
Are there ANY limits on what people can post and does anybody moderate content?
Can one post copyrighted stuff or porn?