Several parts combine into one character.

元 emphasizes the head of a person (儿, legs) with two strokes (二) on top — the original meaning is "head," the topmost part of a person. Since the head is the body's chief and starting point, the sense grew into "first, origin, source." The original meaning survives in 元首 (head of state).

Mandarin: yuán, 2nd tone. Above all, it is the unit of Chinese currency — 元 (yuán), as in 一元 (yī yuán, one yuan). 元旦 (yuándàn, January 1st), 公元 (gōngyuán, the Common Era / A.D.), 元素 (yuánsù, chemical element). It is also the dynasty name of the Mongol-founded 元朝 (Yuáncháo, the Yuan dynasty, 1271–1368).

Japanese: on-readings ゲン (gen) and ガン (gan), kun もと (moto). 元気 (genki, healthy / lively — "source energy"), 元旦 (gantan, New Year's morning), 元 (moto, originally). The first year of a new Japanese imperial era is called 元年 (gannen).

Korean hanja-sound "won": 元來 (wollae, originally), 元旦 (wondan, New Year's morning), 紀元 (giwon, era / epoch). The Mongol Yuan dynasty, which influenced the Korean peninsula between Goryeo and Joseon, is also 元 (Won).

Memory aid: above a person (儿), two strokes (二) pointing at the head — the topmost, the very first.