Birds are one of the most intriguing types of animals in the world. Other than their ability to fly, most birds have unique characteristics that make them interesting subjects of study. Their appearances, breeding and nesting habits, and biological features set them apart from other animals, and they also come in a wide variety of colors and sizes. Birds are so captivating that many people devote a lot of time to bird-watching, so that they can observe and learn about the behaviors of different species of birds. Here are a number of websites that provide more information about birds.