"The Fry word list or "instant words" are widely accepted to contain the most used words in reading and writing. The sight words list is divided into ten levels and then divided into groups of twenty-five words, based on frequency of use and difficulty. "
The Dolch Sight word list includes the most common 220 words and 95 nouns encountered in children’s books. Dolch words, or sight words, are critical in early reading development because they represent high-frequency words and are difficult to sound out or to illustrate.