what you post in steemit or send comments to your steem friends.
All content that you produce will remain in steem platform for ever. You don't allow to delete your post. Just you have 7 days time to edit your post. After that, you can't edit the post.
There is no pv or secret chat. Everyone can see all of your comments and replies.
Be care what you write and which picture or video post on the steemit network.
I wish you good chance