A "Proof of Purchase" is a document or item that verifies a consumer has bought a product or service. This can include receipts, invoices, or packaging with barcodes. It is often required for returns, exchanges, or warranty claims, ensuring that the customer has legitimate ownership of the item. Retailers and manufacturers use proof of purchase to track sales and manage inventory. It can also help consumers access customer support or participate in promotions. Keeping proof of purchase is important for both customers and businesses to maintain accurate records and facilitate transactions.