Astrud Gilberto

The endlessly covered Brazilian song turns 50 this year. What explains its quirky endurance?

Amy Winehouse. Ella Fitzgerald. Sammy Davis Jr. The Yale Whiffenpoofs. Mike Tyson.

All of these artists — and non-artists — are members of a big club. They're among many who've crooned the second-most recorded pop song ever, according to a count by Performing Songwriter magazine.