Great explanation, thanks! I got the jist of the story, that Facebook uses MySQL, which is freeware and was never designed for hundreds of millions of users creating billions of transactions; however, I didn’t know that Facebook ran on such a tiny platform!!
A few years ago I worked for a huge financial company, and learned that a key list of company information was kept on one of the employee’s desktop computer hard drive, in a spreadsheet!
Don't laugh. Just a couple days ago, a dental person asked about the programming business. I told her that pretty soon, American programmers will be helping people run their businesses on Excel spreadsheets, powered by off-the-grid mini-solar panels, without any internet to be found. She didn't laugh, and I didn't mean it to be funny.