TurtleCoin Software Basics
What is a Privacy Blockchain?
TurtleCoin is a privacy-focused blockchain. As we discussed in the last exercise, nobody can look up your TurtleCoin balance or your transaction history unless you give them your keys, and nobody can go back and reverse a payment they made.
How does this work?
When a transaction is sent, the money being sent is mixed a few times with money from 3 random users on the network behind the scenes, and only the funds being sent actually move. As your money arrives at the destination, nobody but you can prove you sent it. Each coin has a sort of serial number on it, but each time the funds move, that number changes, which means every coin is indistinguishable from another. This concept of indistinguishable coins is called “fungibility”, and that mixing technology baked into every transaction is called “Ring Signatures”.
TurtleCoin is different than Bitcoin in this way, because Bitcoin has no Ring Signatures and is not fungible. Using anyone’s publicly available Bitcoin address you can look up their transactions and who they’ve sent money to, and how much money they have, and so forth. Imagine if your bank account worked this way!
TurtleCoin is also a “blockchain”. Remember when we said that TurtleCoin processes a block of transactions every 30 seconds? We chain each block to the one before it, in a way that every new block’s ID is made from the ID before it, and so on. This creates an unbreakable chain of transaction history. This means that nobody can go back and alter the records of a transaction or take the money back, because each block of transactions after builds on top of it.