Many (some reports put it at very nearly all) of us, use social media in some form or another daily. For all sorts of reasons. There are lots of studies about the benefits of drawbacks of social media, but one potential huge drawback is increased privacy and security concerns and the way social media opens us up to new dangers.
There are ways to stay safer as we engage:
Note that in some cases, things like your birthday (how easy it to say "I'm 21 today!" or have Facebook simply make friends birthday posts exposing your age/details public information on your profile) can be used to spoof you online and sometimes is one of the few key pieces of information used to verify it is "you" if someone is trying to access some accounts. Posting your location in real time (such as vacation shots, being on flights, or even just saying you are going to the cafeteria for lunch) can be used by folks to identify when you are not at home or by stalkers to track you. Keep that information friends only, in other words.
One of the surprising flaws of social media is that sometimes the fun, social parts of them have complicated relationships with online security. As mentioned above, innocuous sharing of your birthday or vacation can lead to security complications. But that is unfortunately not all that can lead to problems. How many times have you seen an online "chain quiz" that asks you to post stuff like:
While many of the questions (and the majority of such quizzes) are innocuous, note that some of those questions (first car, first pet, and, depending on how you answer it, even where you grew up) can be used to answer common security questions about yourself. Even something like "favorite book" can be used to help answer a security question like "favorite character".
Sometimes, you get examples that say things like, "Use the month you were born to pick a color and the day you were born to pick a type of vehicle and that's your ride of the future!" With that information, combined with things like age or other posts, someone can work out your exact birthday.
Is any of this an actual sign of trouble and should you be concerned because you answered one of those years ago? Maybe not, but hackers do use these quizzes to build up information about you and even find precise answers to your security questions. This information can make you the target of phishing attacks, and have accounts you thought were you secure become compromised. Again, the trick is not to avoid it altogether, but to take note of privacy settings and to use caution.