Google knows a lot about its users. Facebook knows a lot about its users. FitBit knows a lot about its users. And so on.

But what happens when these companies all sell their data sets to one another? It'd be pretty trivial to link even anonymized users from set to set by looking for specific features. If I went for a run, Google tracked my location, FitBit tracked my heart rate, and Facebook tracked my status about my new best mile time, for example. Thus, Google can narrow down who I am in the other sets using pre-existing information that coincides with theirs. With enough overlap they can figure out exactly who I am fairly easily. Furthermore, each additional layer of data makes this discovery process from new data sets even easier, as it gives more opportunities to confirm or rule out concurrent info. So then when, say, Credit Karma, Comcast, and Amazon's data enter the fray, my online identity stops looking like an individual egg in each different basket but a whole lot of eggs in all in one. And they can do this across millions/billions of users--not just me!

I don't know for certain that this is a thing that happens, but... I have to assume it definitely is happening, right? How could it not? With how valuable data is and how loose protections are, this seems like a logical and potentially very lucrative step.

Right now, is there an aggregate version of "me" that exists in a data store somewhere that is a more comprehensive and accurate picture than my own self-image? After all, my memory and perception are imperfect and biased, but data stores aren't.

Over the past year I have done a lot to shore up my digital privacy and security. One of the last tasks I have to tackle is locking down the many personal files I have on my computer that have potentially compromising information in them (e.g. bank statements). Right now they are simply sitting on my hard drive, unencrypted. Theft of my device or a breach in access through the network would allow a frightening level of access to many of my records.

As such, what are my options for keeping certain files behind an encryption "shield"? Also, what are the potential tradeoffs for doing so? In researching the topic online I've read plenty of horror stories about people losing archives or whole drives due to encryption-related errors/mistakes. How can I protect against this scenario? Losing the files would be almost as bad as having them compromised!

I'm running Linux, but I'm far from tech-savvy, so I would either need a solution to be straightforward or I'd have to learn a lot to make sense of a more complicated solution. I'm willing to learn mainly because it's not an option for me to continue with my current, insecure setup. I do use a cloud-based password manager that allows for uploading of files, and I trust it enough with my passwords that I would trust it with my files, though I would like to avoid that situation if possible.

With all this in mind, what's a good solution for me to protect my personal files?

It's hard to get a straight answer on this because there are allegations of shilling everywhere when it comes to VPNs (particularly when you discuss specific providers). There's also this post which gets linked pretty frequently and which seems to throw a wrench in the whole idea.

For context, I ask because I have two main concerns:

1. I have been the subject of a mild internet stalking/doxing, and I have no wish to relive that experience.
2. I live in the United States and, if I am understanding things correctly, my ISP now has the right to sell my browsing data without my consent.

I have no love for my ISP and am all about the idea of blocking them from gathering data about me, but it seems the only other option is to hand all of my data over to another company who simply promises not to do anything with it. While I'm sure some of them are legitimate, how can you tell the difference between a genuine privacy tool and a honeypot?

Here is what just happened to me:
Firefox installed two addons - fxmonitor@mozilla.org.xpi and telemetry-coverage-bug1487578@mozilla.org into my browser silently, even though I've explicitly turned all the telemetry off.
This have happened before, and Mozilla apologized for it, however it seems that they learned nothing and are willing to do so again.
There goes the last scrap of my trust into Firefox. I suggest you check your browsers too.