Several parts combine into one character.

帽 has an etymologically rich double-marking structure. The right component 冒 (mào) was originally a pictograph of a hat covering the eyes — the character itself, before any radical was added, depicted a head with a covering pulled down. As the meaning of 冒 drifted toward "to risk / brave / cover boldly," the cloth radical 巾 was added on the left to reclaim the literal "hat" meaning. So 帽 is unusual — its right side once meant exactly what the whole character now means, and the cloth radical is essentially redundant clarification. The repetition is etymologically fitting: the character points twice toward "head-covering."

Korean reading "mo." 帽子 (moja, hat — the standard Korean Sino-Korean term, more common than the pure Korean equivalent 갓 which now refers specifically to traditional Korean horsehair hats), 軍帽 (gunmo, military cap), 安全帽 (anjeonmo, safety helmet — used on construction sites), 黑色帽 (heuksaegmo, black hat). Korean keeps 帽 in active formal-compound use.

Mandarin mào, 4th tone. 帽 (mào), 帽子 (màozi, hat — the everyday word in Mandarin, exactly mirroring Korean 모자), 棒球帽 (bàngqiúmào, "baseball-hat" = baseball cap), 安全帽 (ānquánmào, hard hat / safety helmet). The compound 戴帽子 (dài màozi, "to wear a hat") in Cultural Revolution-era Chinese took on a sinister metaphorical meaning: "having a label / political accusation pinned on you."

Japanese on-reading ボウ (bō) — 帽子 (bōshi, hat — also one of the first nouns Japanese learners memorize at N5 level), 赤帽 (akabō, "red cap" — the traditional name for the porters at Japanese train stations who wore distinctive red caps; the word now lingers in nostalgia and in the moving company brand "Akabō" that carries luggage), 脱帽 (datsubō, "to take off one's hat" = "hats off!" / a sign of respect or admiration; also used to mean "I surrender, you win this argument"). Japanese has essentially no kun-reading for 帽 — almost all usage goes through ボウ.

Memory aid: cloth (巾) plus 冒 (a head with a covering pulled down) — the cloth radical doubles down on the original "hat" meaning embedded in 冒.