|"The blockchain" is getting bounced around at my work a bit as a solution for a problem we don't actually have. I personally don't understand it and am looking for some assistance.
I've read a bunch of material on "the blockchain" and have watched a number of videos on the thing, and while I get it in a rough sense, I don't "get it" get it.
It seems to me like it is, in essence, a distributed database that can only have records added to it, and nothing changed. It's also apparently meant to be completely open and visible so that people can see what has gone before.
1) Is the blockchain (whichever blockchain) just one big file? Or is each "block" distributed wherever, and "chained" to previous blocks via essentially a newer version of a TCP/IP header/footer?
1a) If the first, how could a single file with anticipated millions of transactions a second even be stored anywhere? Servers would melt through the floor.
1b) If the second, how is that secure?
2) It is touted as the most secure thing that was ever secured, but could somebody not simply lie in their "block"? One example in one of the many videos I watched - which I admit I have fixated on, perhaps detrimentally, while missing the bigger picture - talked about the origin of "free trade" coffee, and how it can somehow magically be verified by the blockchain. But if I was a dodgy free trade coffee manufacturer, I would simply lie at the outset ("Yes, this stuff is totally legit. Upload!"), and that would ruin the blockchain...wouldn't it?
3) If it is open and transparent, how is that secure? If it is truly secure, how can it be open and transparent?
I apologise, I am probably coming off like the world's biggest doofus, but even the Wikipedia article basically talks about what blockchain DOES (or is predicted to do) rather than what it IS. I guess I am stuck in my old Windows network administration thought patterns, and I am desperately hoping for an "aha!" that will make it clear to me.
(To demonstrate my openness about being a doofus, when I was fifteen I sent a paper letter to a PC magazine asking if a 100MB hard drive full of data would weigh more than a 100MB hard drive that had been freshly formatted. The rest of my life has been just winging it.)
Thanks in advance.