Robert Plant may be 63 years old now, but the former Led Zeppelin singer is still in possession of a voice that is as distinct and instantly recognizable as a fingerprint. Even though he is in the sixth decade of his life, Plant's voice is aging like a fine wine or cheese; as he gets older, it many ways, it actually gets better.

Plant told VH1 Radio that the evolution of his voice is similar to playing an instrument, namely the guitar. "It's like playing a guitar: the more you play, the more dexterous you become, the more your fingers move faster and all that sort of thing," the singer said.

He also acknowledged that his voice is different at this point in his life, saying, "My voice has changed but I can go to high places if it's what I have to do." We don't doubt that, in fact we witnessed it for ourselves on the closing night of his most recent U.S. tour.

Changed or not, Plant's voice remains one of the most definitive in rock music. In fact, in honor of his 63rd birthday yesterday (Aug. 20), we decided to ramble on a bit about our choices for the 10 Best Robert Plant Songs.