Several parts combine into one character.

The oracle-bone 無 showed a person dancing with long feather plumes held in both hands — it was originally the ancestor of 舞 ("to dance"). When the graph was borrowed for the same-sounding word "to not have", the dance meaning split off into 舞 (with 舛, dancing feet, added below). The four dots at the bottom (灬) are not fire — they are the frozen remains of the dancer's legs and trailing sleeves.

The simplified form is 无, a revival of an ancient minimal variant that looks nothing like traditional 無. This is one of the characters whose shape diverges most sharply between scripts.

Mandarin: wú, 2nd tone. 无聊 (wúliáo, bored), 无论 (wúlùn, no matter / regardless), 无法 (wúfǎ, unable to). It is the negation that opens onto philosophy: Daoist 无为 (wúwéi, non-action), Buddhist 无常 (wúcháng, impermanence).

Japanese: on-readings ム (mu) and ブ (bu); kun な.い (nai, to not be). 無理 (muri, impossible / unreasonable), 無料 (muryō, free of charge), 無視 (mushi, to ignore). The central Zen kōan is simply 無 (mu) — "nothing", the answer that is no answer.

Korean hanja-sound "mu": 無料 (muryo, free), 無限 (muhan, infinite), 虛無 (heomu, nihility). "Not-having" is a keyword of East Asian thought.

Memory aid: the dense top is the bundle of feathers a dancer holds; the four dots below are the feet. A character borrowed from "dance" to mean "none".