Several parts combine into one character.

社 has 示 (altar / to show) for meaning and 土 (earth) lending both sound and sense. It originally meant an altar of heaped earth (土) for worshipping the god of the local soil — the place where villagers gathered to sacrifice to the land-spirit. From that gathering grew the sense "association, society, organization."

Korean hanja-sound "sa": 會社 (hoesa, company), 社會 (sahoe, society), 社長 (sajang, company president), 新聞社 (sinmunsa, newspaper company). Strikingly, the same two characters reversed give 會社 (company) and 社會 (society).

Mandarin: shè, 4th tone. 社会 (shèhuì, society), 社区 (shèqū, community / neighborhood), 社交 (shèjiāo, social interaction), 合作社 (hézuòshè, cooperative). Note that "company" in Mandarin is 公司 (gōngsī), not 社.

Japanese: on-reading シャ (sha), kun やしろ (yashiro). 会社 (kaisha, company), 社会 (shakai, society), 神社 (jinja, Shinto shrine), 社長 (shachō, company president). The kun やしろ means a shrine housing a god, keeping the original sense (an altar to the soil-god) alive.

Memory aid: earth (土) beside an altar (示) — where people gathered to sacrifice to the god of the land.