M66 is a very good example of the dynamics that gravitational interaction with other galaxies can produce. Nearby, at least in terms of galaxies, are two other island universes, forming a group popularly known as the Leo Triplet. The interaction disturbs the delicate structure of the galaxies, warping (and possibly even causing) the spiral arms, and triggers episodes of rapid and widespread star formation. We see this here as clusters of hot, young blue stars, and pinkish regions of energized hydrogen gas, clouds illuminated by still younger stars just being born.