What makes Free by Chicago notable?

'Free' is significant for showcasing Chicago's growth as a band and achieving commercial success, peaking at number 14 on the Billboard Hot 100. The tracks from this album laid the groundwork for their future work and solidified their place in the adult contemporary music scene. Released on February 1, 1971, 'Free' marked Chicago's transition into a more sophisticated sound following their self-titled debut in 1969. At this point, the band was beginning to establish its identity, moving beyond their earlier rock roots into a unique mix of jazz and pop elements that would define their career.