How Do You Define Your Privacy?

Have a facebook and am fairly active on it. (Tech Savvy young gun here) However, I don't post every random thing that comes into my head. Hell, my last post that I genuinely thought up was back on V day. However I usually post once every couple days if something interesting happens. Which usually isn't very interesting, but I feel like saying it. When I went over to my ex's house, her parents, sister, and older brother's gf were all on their phones all the time while watching TV. And all they were doing 90% was just browsing. I only have an iPod touch so without WiFi I really can't do anything except listen to music. And really, when people are on their phones all the time, half the time they are just going through their wall seeing what other people are saying or sharing pictures. I very rarely see my friends post many many times a day unless it's to share things. And I do not have any personal information on there other than my name and birthdate, and basic city area I'm in. On the fabo member map, I put my pin somewhere I'm not but roughly in the same area.