Pretty much every aspect of your life generates data that is valuable to someone. What coffee shops do you pass on your way to work? Your shopping habits, your income, etc. All of these can be used for targeted advertisements or nefarious acts. Controlling how your data is used is imperative for protecting yourself, not just online but in general.
While you do have some control over how your data is used or collected, in many instances, handing over some of your personal data is just a cost of doing business with an organization. With that being said, you have a choice regarding who you do business with. A decision must be made whether the service being provided is worth the data you are handing over.
The National Cyber Security Alliance has provided a short, non-inclusive list of things to think about and implement in your life to better safeguard your data privacy. While following this list won’t solve all of your data privacy issues, it will put you in the right mindset to better protect yourself moving forward.