Male and female canary
This male (yellow) and female (gray) canary are one species of song bird.

Interestingly, scientists have found that songbirds  learn language in a way that is similar to how humans learn language.

There are over 90 species of songbirds and they all have unique songs. For instance, hummingbird songs sound more like an insect sound, whereas canaries sing melodies that are learned new each season. Mockingbirds sing songs which copy the sounds of other birds in the area. 

Click on this link to hear a cardinal song.