In broad terms, literacy is the ability to make and communicate meaning from and by the use of a variety of socially contextual symbols. Within various levels of developmental ability, a literate person can derive and convey meaning, and use their knowledge to achieve a desired purpose or goal that requires the use of language skills, be they spoken or written. A literate person can mediate their world by deliberately and flexibly orchestrating meaning from one linguistic knowledge base and apply or connect it to another knowledge base. For example, knowing that letters symbolize sounds, and that those sounds form words to which the reader can attach meaning, is an example of the cognitive orchestration of knowledge, a literate person conducts. Literacy is "not in isolated bits of knowledge but in students' growing ability to use language and literacy in more and broader activities" (Moll, 1994, p. 202).The definition of literacy is dynamic, evolving, and reflects the continual changes in our society.  Literacy has, for instance, expanded to include literacy in information and communication technologies and critical literacy (Cunningham, 2000; Harste, 1994; Leu, 2002; Mol1, 1994; Paris, Lipson & Wixson, 1994; Yopp & Singer, 1994).