The only thing more intimidating than tech and finance is tech and finance combined… so yeah, blockchain used to feel super unapproachable to me. In Day 0 of my 10 Days of Blockchain series, I’m breaking the buzzwords down into actual English: centralization vs decentralization, what a “ledger” really means, and how blockchain is basically a shared, constantly-updated record across a network—not one magical server somewhere. I start with a simple example: working on a file locally vs putting it on Google Drive. Even if you can edit from anywhere, it’s still centralized because the “best” version lives in one place. Then I take that idea to the extreme: what if every machine had the most up-to-date copy and validated changes together? That’s the mental model you need for Bitcoin (a decentralized currency), and it’s also how blockchain works under the hood: blocks contain transactions, and as more blocks get added, it gets harder to rewrite history. Finally, I zoom out to DApps (decentralized applications). Transactions don’t have to be money—they can be any state change, like incrementing a counter. And because blockchain dev can require specialized languages and a lot of ramp-up, I introduce Reach and Algorand (our sponsors) and explain how Reach lets you build once and deploy to multiple chains. Next video: we set up the environment and start building.