The BCG Matrix, developed by the Boston Consulting Group, is a strategic tool used to evaluate a company's product portfolio. It categorizes products into four quadrants based on market growth and market share: Stars, Question Marks, Cash Cows, and Dogs. This helps businesses identify which products to invest in, maintain, or divest. In the BCG Matrix, Stars are high-growth products with a strong market share, while Cash Cows are established products with low growth but high market share. Question Marks have potential but require investment, and Dogs are low-growth, low-share products that may be candidates for discontinuation.