Most HFW are decodable. Research shows that our brains need to go through the process of making the letter-sound connections in order for these words to stick. We call this orthographic mapping. Kilpatrick (2015) describes orthographic mapping as "The mental process we use to permanently store words for immediate, effortless retrieval. It is the process we use to take an unfamiliar printed word and turn it into an immediately recognizable word." We want kids to go through this process many times so that a word eventually becomes a sight word!