Ratio analysis is a technique that measures the financial strength and weaknesses of an organization using ratios calculated from information in the balance sheet and income statement. There are various types of ratios that serve different purposes, such as liquidity ratios that measure short-term solvency, activity ratios that measure efficiency, and profitability ratios that measure long-term performance. While ratios provide quantitative measures, they also have limitations such as being based on historical data and different interpretation.