Cockatoos are parrots. What distinguishes them from other parrots is their crest, which they can move and which they use to show emotions. And they have gall bladder, unlike other parrots. And they are endemic to the island of the South Pacific, whereas most other parrots are endemic to South and Central America.
The word ‘parakeet’ is a general name for small parrots such as budgerigars and cockatiels.
I photographed this cockatoo with a Nikon D500 with a 70-300mm lens at 200mm f6.3 1/640 second and ISO 1600. And what I learned from this shot (a lesson I keep having to learn) is to get enough light on the subject. Underexposure kills the quality of the image. But not with this shot. Click the image to see a larger version and how sharp it is.