I'm not on any of the social medias but that doesn't mean I'm not safe. Many of us are by reference of family, friends and business acquaintances, present on facebook, twitter, pinterest and others. Even people who don't even have computers.
The commentary said they collect information not limited to, but including names of family, friends, addresses, phone numbers online friends that you may have never met. I'm sure they use key words, so all anyone would need do is post a word that might be considered racial, anti-LGBT, infer violence, drugs, guns, or almost anything, since people today are offended by almost anything.
