Subsidiary Books are the books used to maintain the Original Entry of anything. Subsidiary Books are also called Day Books. The different types of Subsidiary Books are-Cash Book- Cash Book registers all the cash and bank receipts and payments of a business or an organization. Cashbook contains all the original entries that are recorded as transactions. Cashbook contains both debit and credit.Purchases Return- Purchases Return is used when the items purchased on credit are returned back to the supplier. This can happen due to various reasons like faulty items or wrong items, etc. Purchase return also records the net amount on all invoices.