During the process of uploading photos you can select the privacy you want for the photos. You can change the privacy of a photo after it has been uploaded.
1. Log in and select Photos.
2. Select the folder where the photo is located.
3. Hover over the photo and you will see the information i in the top left corner. Click on it.
3. Click on the lock icon to see the privacy menu.
3. Select who can view your photo. If you do not want anyone else to see your photo, select Private/Only Me.
4. Close out of the box and your privacy setting is automatically saved.