ROI, or Return on Investment, is a key performance indicator used across various functions within any organization to measure the profitability of an investment. From a digital marketing perspective, ROI helps you evaluate whether the expenditure on marketing activities is justified by the resulting sales and revenue generated. By comparing the net profit of these activities to the total cost incurred, marketers can assess the effectiveness and efficiency of their campaigns. For example, if you spend $1,000 on a digital ad campaign and generate $5,000 in sales, your ROI would be 400%, indicating a high return. This metric is essential for optimizing budgets, guiding strategic decisions, and ensuring that marketing efforts are aligned with business goals to maximize profitability and growth.