The Wall

Blockchain is hard to explain via post-it. Let’s say I spend money from my bank account in January and make a document with all of my transactions: how much they were, who I paid, etc. I can continue to add to that ledger throughout my lifetime, but it eventually gets to be such a big file that I can’t move it anywhere. In order to make it smaller, I can take chunks of a ledger (say January only) and create hashes (unique IDs based on the contents of the file). Then I can add the hash of all of the January transactions to my February ledger and I now know where to look for January’s if I want to go back that far. The same is true for March, I can add the hash of February, which also contains the hash of January’s transactions. This is where the “chain” part comes in, you’re creating a chain of pointers back to blocks of information all the way back to the beginning. A (better) simple explanation can be found here: bit.ly/blockchainsimple. Princeton has a great and VERY detailed video series on blockchain here: bit.ly/princetonblockchain