The meatiest parts of a bird are the flightmuscles on its chest, called breast meat, and the walking muscles on the first and second segments of its legs, called the thigh and drumstick respectively.
White meat has less oxygen-carrying myoglobin than the walking muscles, or dark meat, and is thus lighter in color. Dark meat tends to come from muscles more heavily exercised, which therefore also have more fat stored in them. This accounts for both dark meat's reputation as being unhealthier, and yet better-tasting.
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