Standing in for real text with placeholder content, nonsense words or gray bars, so a layout can be judged before the copy exists.
Greek everything below the fold; this review is about the structure, not the words.
The name comes from “it’s all Greek to me,” and the most famous greeking text is Latin. The practice has always outrun its etymology. Greeking is honest early, when it keeps a review pointed at structure instead of word choice, and dishonest late: lorem ipsum never produces a widow, never overflows a button, never arrives in German. A layout isn’t finished until real content has tried to break it.