A group of computers is connected together in a system called a "network of nodes." Each computer in the network is called a "node." The nodes connect to the Blockchain using a program called a "client." The client helps make sure the transactions on the Blockchain are correct. When a computer joins the network, it gets a copy of all the information on the Blockchain. The nodes work together to make sure they all have the most recent information. Some of the nodes, called "miners," help process transactions and are rewarded for their work.