Back to basics: Johann Sebastian Bach wrote 15 of these "Inventions" in his son's score book as exercises. They are full of clever musical inventions in counterpoint which was the dominant style during the Baroque period. No 1 in C major uses only a short subject as the foundation for the whole piece, to which Bach applies appropriate mechanisms of transformation. Pianist Henrik Kilhamn plays together with an analysis.
Youtube video: https://youtu.be/HXQJpWTDrt8