"Unforgettable" is the most famous song of Nat King Cole, an American singer, pianist, and jazz musician. The song was originally recorded by Nat King Cole in 1951, and it became his signature song. It was written by Irving Gordon, and it was inspired by Irving Berlin's song "Remember". "Unforgettable" was a huge hit for Nat King Cole, and it reached the top of the charts in many countries. The song has also been covered by many other artists, including Frank Sinatra, Ella Fitzgerald, and Elvis Presley.