"Skip to My (The) Lou" is a popular American partner-stealing (or swapping partners as in square dancing) dance from the 1840s. The "lou" in the title comes from the word "loo", a Scottish word for "love".
These types of American musical short features were called 'Soundies', and consisted of three-minute musical 16mm films, produced in New York City, Chicago, and Hollywood, between 1940 and 1946, each containing a song, dance and/or band or orchestral number. The name "Soundies" was generalized to any similar film since most productions were made available for rental by the Soundies Distributing Corporation of America.