Birds are considered warm-blooded vertebrates, and they are among the most diverse animals, with more than ten thousand and 400 live species, in addition to more than 1000 extinct species.  All birds share a unique feature that distinguishes them from other animals, which is the presence of feathers that cover their body, and although their heart is made up of four chambers, as in mammals, they are closer and more closely related to reptiles than to mammals, all birds have wings, and lay eggs covered with a hard shell,  They also have a strong sense of vision, while the senses of smell and hearing are less developed.

 * Many people want to have a pet at home, and when thinking about the available options, birds are among the most beautiful things that can be acquired. They are distinguished by their beautiful colors, and the often sweet sound of their tweet.  The types of birds differ, their shapes, and sizes, and most of all, they differ in their prices. Some birds can be obtained for low amounts, but some birds are sold at very high prices

 1- Racing Pigeons: The racing pigeon Bolt, named after the fastest runner in the world "Usain Bolt", is the most expensive bird in history, and the pigeon Bolt sold for 410 thousand US dollars, while racing pigeons can usually be bought  At a price of $ 90 thousand, it ranks first in the list of the most expensive birds.

 2- The black palm cockatoo, or the black palm cockatoo: (English: Black Palm Cockatoo) is a bird of the order of parrots, and the cockatoo family, whose length ranges between 22-24 inches, is distinguished by the color of its gray plumage, its large beak, and with two red spots on the cheeks, laying a female  Palm parrot one egg per year, so this type of rare bird is sold at a price of 17 thousand dollars.  This parrot is found mostly in the Arrow Islands, New Guinea, and Cape York Peninsula.

 3- Toucan: (in English: Toucan) The toucan bird, which belongs to the family of Ramphastidae (English: Ramphastidae), is one of the most beautiful birds, as it is distinguished by colorful feathers that cover the wings and legs, and its long beak is colored with a mixture of attractive colors.  The beak of the toucan is the longest in the class of birds.  The toucan, which is often found in the Caribbean, South America, and southern Mexico, sells for ten thousand dollars.

 4- The Sapphire Macaw: (English: Hyacinth Macaw) The Sapphire Macaw is the longest species of parrots. Its body length reaches 100 centimeters, and its weight ranges between 1.2 - 1.7 kilograms. The Sapphire Macaw is distinguished by its very strong beak that enables it to eat palm tree nuts.  And eastern South America, and one of them sells for nine thousand and 500 dollars.

 5- Pink flamingo, or flamingo: (English: Flamingo) The flamingo bird is one of the most beautiful and largest birds in size, its feathers are beautiful pink in color as indicated by its name, and there are almost six types of flamingo, and the speed of the flamingo reaches 35 miles per hour,  Flamingos are often seen standing on one leg in order to get more heat, and fetch up to $ 1,000.

 6- Scarlet Tanager: (English: Scarlet Tanager) is a small songbird whose length ranges between 16-19 cm.  Vermilion Tangerines live in cool temperatures, and sell for $ 900.

 7- Northern Oriole, or Northern Oriole: (English: Northern Oriole) is a strong, medium-sized bird whose length ranges between 17 - 23 centimeters, and with an average weight of 33.8 grams, its males are slightly larger than the females, and it has long legs, and is distinguished by a beautiful voice.  Its price reaches 850 USD.

 8- Mountain bluebird: Mountain bluebird is distinguished by its blue and black eye color, and it is a medium-sized bird.  The average length of its body ranges from 16 to 20 centimeters, and it weighs 30 grams, the color of the body is pale blue, and the male is distinguished from the female by the fact that the wings' feathers appear in a bright blue color, this beautiful bird lives in North America, including Alaska, and feeds on locusts,  Insects, spiders and flies, it is sold at $ 850.

 9- The North Cardinal: (English: North Cardinal) is a bird distinguished by its golden-colored beak and beautiful color of its feathers. The weight of the lightest members of this type of bird is 85 grams, while its body length reaches 12 centimeters.

 10- American goldfinch: It is also called the eastern goldfinch, and it is a bird that lives in North America and migrates to northern California during the breeding season, and feeds on fruit seeds, and its price is the lowest on our list, at approximately $ 765.

 * The hummingbird is the smallest bird in size, while the largest birds are the ostrich, and the emu.  The peregrine bird is the fastest living animal ever.  It has an average speed of 200 kilometers per hour, and its speed reaches 350 kilometers per hour when swept.

 * The bird's body adapts to flight, it has a solid skeleton, and the bones are hollow to reduce the weight of the bird.  Some types of birds have a symbiotic relationship with other animals, some of which feed on parasites that are found on the skin of the rhinoceros, and some feed on the parasites in the mouth of the crocodile.  Most birds are diurnal active, but some are like owls,

 * The slave bird is active at night or during twilight hours.  Bird feather color patterns differ according to the environment in which they live, as they act as camouflage against predators.  The number of cervical vertebrae ranges between 13-25 vertebrae, and thus their number is more than the number of cervical vertebrae of many vertebrate animals.

 * Birds consume a lot of energy during flight, so their respiratory system is highly efficient to provide the body with the oxygen needed for metabolism and the release of energy.  91% of bird species in the world are considered monogamous, meaning that they mate with only one partner, and this type of mating is necessary for the parents to be able to take care of their young together, as females cannot take care of the young without the male,