The Samsung Galaxy S21 is a compact 5G flagship smartphone (released 2021) featuring a 6.2-inch 120Hz AMOLED display, Snapdragon 888/Exynos 2100 processor, and a durable, sleek design with a plastic back. It offers a versatile 64MP triple camera system, 8GB of RAM, and 128/256GB storage, known for excellent performance, 4K video, and all-day battery life.