Watercolor pens are art tools that combine the ease of a pen with the fluidity of watercolor paint. They typically contain water-based ink that can be blended with water to create soft, flowing colors. Artists and hobbyists use these pens for various projects, including illustrations, card making, and journaling. These pens come in a variety of colors and tip sizes, allowing for detailed work or broad strokes. When used with a brush or water, the ink can be manipulated to achieve different effects, making them a versatile choice for both beginners and experienced artists.