most kanji characters can be pronounced at least two different ways according to whether the word is a native japanese word (this is called the “kun” reading, or “kun-yomi”), or whether it came from chinese (this called the “on” reading or “on-yomi”). kanji that stand alone usually have kun-yomi, while kanji compound words usually have on-yomi. for example, 山 on its own is "yama" (the japanese word for “mountain”). when it is combined with another word or name, it is pronounced "san" e.g. “fuji-san” (mount fuji).