Millets are nutrient-dense small-grained cereals that have gained attention for their potential in promoting food and nutritional security. They are rich in dietary fiber, proteins, minerals, and bioactive compounds and are gluten-free, making them suitable for functional foods and special diets. This review provides an overview of millet processing techniques, their impact on nutritional quality, and the scope of fermented millet-based products. Various processing methods such as milling, germination, malting, and extrusion significantly affect the bioavailability of nutrients and anti-nutritional factors. Fermentation further enhances nutritional quality, digestibility, and shelf-life, and also contributes to the development of novel functional foods. The review highlights the potential of millets as sustainable food sources and their applications in health-promoting diets.