Security: is when your communications or interactions with things online, are safely routed to the internet against adversaries (e.g. hackers, eavesdropping by governments). You are sure you are interacting with the service or people you want to be interacting with, without that failing underneath you. Security involves cryptography, the ability to take a message that is humanly legible and scramble it so that only the intended recipient can unscramble it.
Privacy: a social contract with the services and machines that we use. Privacy with the services we use, our data isn’t turned around and monetized behind our backs. Another principle is about how well a service can protect us from other people who might wish us farm e.g. prevention from being stalked or harassed online. Tension between a service (e.g. Facebook) and your right to privacy as an internet user.
How to center privacy and security?
Security and privacy are closely interlinked.
Data protection by design and default