Birds are a diverse group of vertebrates that are found all over the world. They are warm-blooded animals with feathers and wings, and most of them are able to fly. Birds are adapted to a wide range of habitats, and they can be found in forests, grasslands, deserts, and even in cities.

There are over 10,000 known species of birds, and they vary greatly in size, shape, and color. Some common examples of birds include robins, sparrows, crows, and seagulls.

Birds play important roles in the environment as pollinators, seed dispersers, and predators of insects and other small animals. They are also popular pets and are often kept in homes, aviaries, and zoos.

Birds have a variety of vocalizations, including songs, calls, and screams, which they use for communication and territorial defense. Some birds, such as parrots and songbirds, are known for their ability to mimic human speech and other sounds.

Most birds have a skeleton that is highly adapted for flight. Their bones are lightweight and hollow, and their wings are made of feathers that are arranged in a way that allows them to produce lift and propel themselves through the air.

Birds have a well-developed respiratory system that helps them breathe while flying. They have a network of air sacs throughout their body that helps to circulate air and oxygenate their tissues.

Birds have an exceptional sense of vision, which allows them to locate food, navigate long distances, and identify predators. Some birds, such as eagles and owls, have eyes that are adapted for hunting at night.