Pigment-based ink is a type of ink that uses tiny solid particles, or pigments, suspended in a liquid. These pigments provide vibrant colors and are known for their excellent lightfastness, meaning they resist fading when exposed to sunlight. This makes them a popular choice for printing photographs and artwork that need to maintain their quality over time. Unlike dye-based ink, which dissolves in liquid, pigment-based ink sits on top of the paper, creating a more durable finish. This characteristic allows it to work well on various surfaces, including canvas and photo paper, making it versatile for artists and photographers alike.