What social networking site did you explore and what settings in that site should users be aware?
I personally use Facebook, Instagram, and Snapchat, and then manage a Facebook and Instagram account for a school club I supervise. I reviewed my settings and have everything set to private. Friends of friends are allowed to request me to "friend" them on Facebook, but the general public is not allowed to. My posts are only visible by friends, and I turn off the share feature of my posts so they cannot be shared publicly. I also don't have any personal information visible on my profile accounts, and only include the required information (I don't include my city, place of employment, job title, etc.).
Users need to be careful about everything they may be sharing. Facebook, for instance, collects and distributes data if the proper settings aren't selected. Without reading the terms and conditions of any social media site (or any site for that matter), you may be giving up a lot of privacy without realizing it, and that's very scary!