We will start up a local blockchain that behaves like Ethereum, allowing us to test and prototype our smart contracts' behavior rapidly. It provides useful features out of the box, such as logging so we can follow the executions as they happen and pre-funded accounts with their corresponding private keys.
Please Be Warry! Never use or send money to the addresses on mainnet Ethereum. These keys are the same every single time. There are sure to be bots waiting to drain these wallets when funds get sent to them.