Accounts payable and accounts receivable refer to money owed to and by a business for goods and services. Accrual accounting records income and expenses when incurred rather than when payment is made. Key financial documents include the income statement, balance sheet, and cash flow statement, which provide different perspectives on a company's performance over time. Financial ratios analyze relationships between financial metrics and compare performance to peers. Profitability, leverage, liquidity, and operating efficiency ratios assess different aspects of a company's financial health.