Probably nothing, but that depends on your definition. Let’s look at the technicalities.
You have a number of crypto transactions that are bundled together into a block. Then you compute a hash - a checksum - for this block. If the data changes, then the checksum no longer matches. The trick that makes it a chain is to include the checksum of the previous block in the next block.
If someone manipulates the transaction history, they need to recalculate the checksum to match. But then they also need to change the following block and recalculate its checksum and so on.
This is a pruned down version of a Merkle Tree, which was thought up ~50 years ago. It doesn’t have to be a chain. You can allow a block to have more than 1 succeeding block; making a fork. Blockchains are one use of that data structure. Wikipedia lists some others. Git, for example, also uses this.
The bitcoin maker knew to use this trick when he needed it. When Torvalds wrote git a few years before that, he also knew to use it.
When you ask about Blockchain specifically rather than Merkle Trees, you greatly limit what can be done with it. So there aren’t a lot of uses left. Most people would say that a Blockchain is more than just a limited Merkle Tree. When you add in those features, you make it even more specific to the original application. So you are probably left with just crypto.
Probably nothing, but that depends on your definition. Let’s look at the technicalities.
You have a number of crypto transactions that are bundled together into a block. Then you compute a hash - a checksum - for this block. If the data changes, then the checksum no longer matches. The trick that makes it a chain is to include the checksum of the previous block in the next block.
If someone manipulates the transaction history, they need to recalculate the checksum to match. But then they also need to change the following block and recalculate its checksum and so on.
This is a pruned down version of a Merkle Tree, which was thought up ~50 years ago. It doesn’t have to be a chain. You can allow a block to have more than 1 succeeding block; making a fork. Blockchains are one use of that data structure. Wikipedia lists some others. Git, for example, also uses this.
The bitcoin maker knew to use this trick when he needed it. When Torvalds wrote git a few years before that, he also knew to use it.
When you ask about Blockchain specifically rather than Merkle Trees, you greatly limit what can be done with it. So there aren’t a lot of uses left. Most people would say that a Blockchain is more than just a limited Merkle Tree. When you add in those features, you make it even more specific to the original application. So you are probably left with just crypto.