You may have noticed that when you send Noir to another wallet, the transaction details and blockchain explorer return change to your wallet using a different address. The reason for this is the input and output approach to transactions in a blockchain. When you send a transaction, it references the block in which you received those funds. For example, let's say you have two transactions. A deposit to your wallet of 10 Noir and a withdraw of 2 Noir . When you send the 2 Noir , the deposit (input) of 10 Noir will be used, giving 8 Noir back in change. If you do not specify the change address, a random address is generated in the wallet.