Budgerigar info taken from wikipedia because I'm lazy:
The budgerigar (Melopsittacus undulatus) /ˈbʌdʒərɨɡɑr/, also known as common pet parakeet or shell parakeet and informally nicknamed the budgie, is a small, long-tailed, seed-eating parrot. Budgerigars are the only species in the Australian genus Melopsittacus, and are found wild throughout the drier parts of Australia where the species has survived harsh inland conditions for the last five million years. Budgerigars are naturally green and yellow with black, scalloped markings on the nape, back, and wings, but have been bred in captivity with colouring in blues, whites, yellows, greys, and even with small crests. Budgerigars are popular pets around the world due to their small size, low cost, and ability to mimic human speech. The origin of the budgerigar's name is unclear. The species was first recorded in 1805, and today is the third most popular pet in the world, after the domesticated dog and cat.
The budgerigar is closely related to the lories and the fig parrots. They are one of the parakeet species, a non-taxonomical term that refers to any of a number of small parrots with long, flat and tapered tails. In both captivity and the wild, budgerigars breed opportunistically and in pairs.
Alternative common names include shell parrot, warbling grass parakeet, canary parrot, zebra parrot, flight bird, scallop parrot and the alternate spellings budgerygah and betcherrygah. Although more applicable to members of the genus Agapornis, the name lovebird has been applied to them from their habit of mutual preening.
Several possible origins for the English name "budgerigar" have been proposed:
A mispronunciation or alteration of Gamilaraay gidjirrigaa [ɡ̊iɟiriɡaː], possibly influenced by the Australian slang word "budgery", meaning "good".
Similarly, from gijirragaa from the Yuwaalaraay. The nomadic nature of Australia's aboriginals would lend itself to forming common linguistic references, and since none had any written language, differences in pronunciation and the presentation thereof are subjective within the constructs of Western hearing.
A compound of "budgery", "good" and gar "cockatoo". The word "budgery", also spelt "boojery", was formerly in use in Australian English slang meaning "good".
The budgerigar was first described by George Shaw in 1805, and given its current binomial name by John Gould in 1840. The genus name Melopsittacus comes from Greek and means "melodious parrot". The species name undulatus is Latin for "undulated" or "wave-patterned". Gould noted the term betcherrygah was used by indigenous people of the Liverpool Plains in New South Wales. While many references mention "good" as part of the meaning, and a few specify "good bird", it is quite possible that reports by those local to the region are more accurate in specifying the direct translation as "good food". There are apocryphal reports that this could also translate as "tasty treat", implying they were eaten by the aboriginals. However, it is more likely the name derived from their migratory nature. With seasonal changes that left parts of the Liverpool Plains barren, they would move to areas with residual water, that still produced the seeds they sought. By following the birds, the aboriginals could locate water, and also other game and food plants. Thus, the birds could lead them to "good food".