Hello, I am a very new user to Plex. I have put my music and a few movies on line and I enjoy that very much. As I add new movies I want to be able to share content. That is my problem. I also added all of our family pictures. I want to share my music and movies, but not the family pictures. Can I choose what to share, or, can I remove the pictures from the Plex server? How? Thank you!
Mike
You can… both 
When sharing your library with a friend you can either grant them access to all content or a limited number of your libraries.

By unchecking All Libraries Plex will provide you with an option to check which specific libraries to share.
Beyond that you can further restrict the shared content by e.g. ratings or labels.

Example… if you want to share individual family videos of a trip with friends with those friends but not all your other family videos, you can assign a Label tag to those videos and restrict the sharing to that Label.
If you decide that you no longer want certain content on your Plex Server you can delete the entire library:
Tom,
Thank you! You are the man. You told me just what I needed to know. I could not find those answers online to save my life!
Mike