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Safe Practices for Personal Data
This short module covers the basics of personal data on the internet, including how and why corporations seek to collect it.
Personal data is a pretty big umbrella term that covers a lot of different kinds of data. Below is an incomplete list, ranked from most sensitive to least sensitive:
Sensitive Personal Information - Information like bank account numbers, credit card numbers, social security numbers, and health records from hospitals. Most of these are protected by law in some form or another in a pretty cut-and-dried way.
Knowingly-Released Information - Things like public social media posts, location data*, search queries, biometric data (think FitBit), and genomic data (think 23andMe). We know this is being given to the companies who's platforms we're using and generally consent to it.
Unknowingly-Released Information - This is a really big part of it and covers a LOT of different things, including information you consented to (#2 above) being sold to a third party, permissions you "agreed" to that make no sense like location data from a calculator app, or that you agreed to for one purpose, but is being used for a secondary purpose (for example giving Facebook access to your contacts is what allowed Cambridge Analytica to gather data on your Facebook Friends without their consent).
These aren't technical terms as everything that isn't protected by law can, and often is, technically "agreed" to by the user in the Terms of Service (you know, 80 page legal document that you don't read and just check the box agreeing to for every online service ever). All kinds of things can be hidden in there that you may not know about (South Park did an episode on it that was both disturbing AND more accurate than anyone would like to think) and your agreement to it gives the corporations legal cover.
So now that we have a general idea of what kind of personal data is collected, let's move on to why companies collect it. The answer will not surprise you.