All budgies originated from wild budgies in Australia, where they live in flocks in the outback. They come in just one colour form, unlike the many, many colors and varieties of the ones in captivity.
Once the wild budgie was brought into captivity and bred, the occasional mutation occurred resulting in color changes. In the wild these would probably not have survived due to being more obvious to predators, you really do not want to be sticking out like a sore thumb when a bird of prey is flying past! Also, it turns out that budgies just plain prefer the original colour and choose to breed with them over anyone different! (This has to do with ultra violet reflection! Another story for another day...)
As you can see the body colour is a lovely bright light green, with a yellow face.
Along the bottom edge of the face are six small black spots and sitting over the outer of these on each side is a violet cheek patch. From the forehead back and down to between the wings they have black and yellow stripes. The feathers on the wings are blackish with yellow edging, with the long flight feathers being blackish with a thick yellow bar only visible when the wings are extended. The long tail feathers are a lovely dark teal blue, with the tail coverts having a thick yellow bar through them. The eyes have a black pupil surrounded by a white circle called the iris ring. The legs and feet are grey. A male budgie can be recognised by the smooth blue cere (flesh around the nostrils), see the bird pictured above left. While the female has a brown, usually rough cere like the one on the right in the image below.
The young budgie is very similar, but the yellow and black stripes (called barring) starts at the top of the beak rather than the forehead. The juvenile budgie has a pale pinkish, sometimes bluish, smooth cere. Their eyes appear solid black due to a darker iris ring, and their feet and legs are pink.
Now lets go from Wild Budgies back to Budgie Colours
and explore the many captive budgerigar colours.