Different bird species prefer different kinds of seed, and if you give them what they don't want, they won't visit your feeder. Sunflower seeds are the most popular seed because they attract a wide variety of bird species that people find desirable—specifically cardinals, nuthatches, jays, finches and even woodpeckers. Other birds like sparrows, towhees, quail, doves and blackbirds prefer cracked corn. Milo, another favorite seed, attracts some of the same birds that love sunflower seeds and cracked corn. Thistle seed, also called nyjer, is a favorite of finches and will bring them in by the dozens. Seed blends that combine these ingredients, or at least a few of them, draw a wider variety of birds to your feeder, making viewing all the different species more fun.