You can think of a person standing on a board on top of a moving wave. They are not pushing the water along; the wave carries them. They stay on the surface, ride this one as far as it goes, and then look out for the next one.
可以想成一個人站在板子上，被一道浪帶著往前。水不是他推的，是浪在推他。他一直停在水的表面，把這道浪衝完，再回頭找下一道。
From the word’s history
Wiktionary records surfer as surf + -er, the ending that names the person who does an action.
Wiktionary 記的是 surf 加上 -er，而 -er 的工作就是把動作變成做這件事的人。所以字面意思就是「衝浪的那個人」，跟核心畫面完全對得上。
Wiktionary entry for surfer (kaikki snapshot 3f6f69a190036ae4): 'From surf + -er.'
登入就可以看每一支怎麼連回核心畫面。