All of them are feathered, winged, bipedal (meaning: having two legs), egg-laying, warm blooded, vertebrate animals belonging to the class Aves.
The unique digestive and respiratory system of the birds help them fly to great heights.
Some birds cannot fly, penguin is one such species.
Some characteristics of modern birds are feathers, beak, egg-laying, high metabolic rate, four-chambered heart, light weight but strong skeleton.
Wings which are actually evolved forelimbs help the birds in their flight.
Though they have similar species, they have certain unique characteristics which differentiate them from others. The birds can be small as much as 2 inches (hummingbird) to as big as 2.75 meters (like an ostrich). Some birds can fly very high and some birds can swim in the water. They have the strong power of monitoring and careful examination is also used as an indicator of the weather conditions.
Birds are also of different colours, some birds like peacock have beautiful and colourful feathers. The presence of peacock symbolizes rain and good weather while owls, bats and vultures are said to indicate a bad, unpleasant weather in an area.
They can fly and go wherever they want to go and move in the air easily.
Birds have wings and feathers, have beaks and claws, they live in the nest. Birds are special kind of animal species with certain specific characteristics which are common in all of them. The bats hang from the branches of the tree upside down.
If parents overlook these bad habits in their initial stages, they will indirectly drive their children to a point of no return.
But if these evils are detected at the very start and nipped in the bud, they can be protected and saved from the possible disasters.