Cash receipts and customer invoices are types of what?

Cash receipts and customer invoices are types of source documents because they serve as the original records from which financial transactions are documented and tracked. Source documents are critical for maintaining the integrity of financial data, as they provide evidence of the transaction's occurrence and the specifics surrounding it, such as the date, amount, and involved parties.

In the case of cash receipts, they confirm that cash has entered the business, while customer invoices represent amounts owed by customers for goods or services provided. Both are fundamental for bookkeeping and accounting processes, as they lay the groundwork for entries made in financial statements and reports.

Other options like budgets, important records, and financial statements each play distinct roles in financial management but do not serve as the foundational evidence that source documents provide for accounting transactions. Budgets are financial plans for future periods, important records could encompass a broader category of documents but lack the specificity of source documents, and financial statements summarize financial data rather than serve as the original documentation of transactions.