Comments everyone can read, friends you actually agreed to, and small groups with their own feed. The rules are short and they are enforced by the server, not by this page.
Anyone on NovaClip can read this.
Swap codes with someone you actually know. They have to accept.
Up to 40 people, its own feed, joined with a code you share.
What the server knows. Your comments, who your friends are and which groups you are in live on NovaClip's server, because there is no other way for another person to see them. Your NovaCoins, your videos and everything in the Editor stay on your device as before. Anyone you add can see your display name and picture — that is the whole point of a friends list, and it is worth knowing before you add someone you have not met.