Definition: Sub-addresses are multiple "alias" addresses automatically generated from a single master account (HD Wallet). Core Logic: All sub-addresses are linked to the same wallet. Any funds received through these addresses will contribute to your total wallet balance. Why use them?:
Privacy Protection ：Using the same address repeatedly allows anyone to track your entire transaction history. Using new sub-addresses makes it much harder to link your activities together.
Accounting ：You can assign different sub-addresses to different senders to easily identify who sent which payment.