The importance of vocabulary knowledge has long been recognized in the development of reading skills. As early as 1924, researchers noted that growth in reading power means continuous growth in word knowledge (Whipple, 1925). Vocabulary is critically important in oral reading instruction. 

There are two types of vocabulary — oral and print. A reader who encounters a strange word in print can decode the word to speech. If it is in the reader’s oral vocabulary, the reader will be able to understand it. If the word is not in the reader’s oral vocabulary, the reader will have to determine the meaning by other means, if possible. Consequently, the larger the reader’s vocabulary (either oral or print), the easier it is to make sense of the text.

• Coming soon: Hints on how to develop oral vocabulary.
• click on Reading Rockets to learn more about research on reading comprehension.