What report provides a summary of income and expenses for a specific period in QuickBooks?

The Profit and Loss Report, also known as the Income Statement, is specifically designed to summarize income and expenses over a particular period. It provides a comprehensive overview of the company's profitability by detailing revenues earned and costs incurred, ultimately showing the net income or loss. This report is essential for assessing the financial performance of a business, as it highlights the ability to generate profit through operations.

The other reports serve different purposes: for instance, the Balance Sheet Report provides a snapshot of a company’s assets, liabilities, and equity at a specific point in time, which does not reflect income and expenses over a period. The Cash Flow Report outlines the inflows and outflows of cash, emphasizing liquidity but not directly summarizing profitability. Lastly, the Sales Report focuses on sales figures and trends, which is only a part of the broader income statement context. Hence, the Profit and Loss Report is the most relevant for summarizing income and expenses within a specified timeframe.