Several parts combine into one character.

Phonetic-semantic compound: 髟 (the "long hair / mane" radical, depicting flowing hair) + 犮 (an old form of 友, providing phonetic value). The encoded meaning: "long flowing hair" → hair on the head. Three forms with significant simplification: 繁體 髮 / 新字体 髪 / 简体 发.

Critical Mainland Chinese complication: simplified Chinese MERGED two unrelated characters into 发. The traditional 髮 (hair, fà 4th tone) and 發 (to send / develop, fā 1st tone) both became 发 in simplified script. So the same 发 character carries TWO completely different meanings, distinguished only by tone: 发 fā (issue / develop) vs. 发 fà (hair). Mainland Chinese learners must absorb this — Hong Kong / Taiwan / Japan still distinguish the two characters visually.

Mandarin: fà, falling 4th tone (simplified 发, the hair-meaning). 头发 (tóufa, hair on head — neutral final tone), 理发 (lǐfà, to cut hair / get a haircut), 染发 (rǎnfà, to dye hair), 长发 (chángfà, long hair), 白发 (báifà, white / gray hair). Note 头发 (tóufa) — "head-hair" — is the everyday word; 髮 alone feels formal.

Japanese: on-reading ハツ (hatsu) for compounds — 散髪 (sanpatsu, haircut), 白髪 (hakuhatsu, white hair), 金髪 (kinpatsu, blonde hair). Kun-reading かみ (kami) is the everyday word — 髪 (kami, hair), 髪型 (kamigata, hairstyle), 髪の毛 (kami no ke, hair strand). Note this kun-reading かみ is identical to the kun-reading for 神 (god) and 紙 (paper) — three meaningful homophones distinguished only by kanji.

危機一髮 (kiki ippatsu, "crisis by a single hair") is a famous four-character idiom — "by a hair's breadth" / "narrow escape".

Memory aid: long flowing hair radical — the locks on a head.

In Japan·髪 = hair (kept distinct from 発 in Japanese)

In China·发 = hair (fà) AND emit/develop (fā) — merged into one form