Twinkle Twinkle Little Star

Or, if you prefer, the French tune Ah! vous dirai-je, Maman, first written down and printed in 1761. Mozart wrote variations on it. Combine it with Jane Taylor's famous short poem (first published in Rhymes for the Nursery in 1806) and you have the ubiquitous Twinkle Twinkle Little Star, as sent up by Lewis Carroll - and beloved of people learning instruments ever since.