end of this continuum, literacy is defined as a psycholinguistic process involving component subprocesses such as letter recognition, phonological encoding, decoding of grapheme strings, word recognition, lexical access, computation of sentence meaning, and so on; at the other end, it is defined as a social practice of meaning construction with distinct characteristics among different groups. Of course, beliefs about effective literacy instruction correlate with these differing definitions. The psycholinguistic definition1 identifies crucial subprocesses in reading; thus in general it tends to support the utility of explicit instruction about these subprocesses (e.g., phoneme-grapheme mapping, word-recognition strategies, identification of derivational morphological relations among words), as well as practice to achieve automatic processing of them. The social practice view assumes that participation in a community that uses literacy communicatively is the crucial precondition for becoming literate; thus this view is associated with instructional practices such as encouraging children to write with invented spelling, exposing children to books by reading aloud, having tapes available, providing classroom libraries, and promoting authentic reading experiences through the use of trade books rather than basal readers. In addition, researchers in the psycholinguistic tradition tend to accept an epigenetic view of reading, in which it is assumed that the learner's (and thus the teacher's) task is different at different stages of development, whereas the social practice view, deemphasizing as it does the individual learner's role, defines no such developmental reorganization.
There has been a vast amount of research related to literacy and literacy instruction. Here we can only provide examples of what has been learned in the various domains of literacy development, focusing on concepts that are relatively well established for first-language reading and their potential relevance for understanding literacy development among bilinguals and second-language learners. We examine in turn prerequisites for the successful acquisition of reading ability, optimal early reading instruction, reading as a developmental process, and psycholinguistic processes of skilled readers.
It is clear that future successful readers typically arrive at school with a set of prior experiences and well-established skills conducive to literacy. The findings in this area are fairly consistent, though explanations of how those prerequisites function to foster literacy development are not. The key prerequisites include an
1There is some confusion in terminology in the field of literacy acquisition. Smith (1983) and Goodman (1968) have called their view of literacy, which in fact lies firmly on the social practice end of the continuum, ''psycholinguistic" to emphasize their claim that literacy acquisition operates in the same way as language acquisition. We reserve the term "psycholonguistic" for views of reading that specify individual processes of graphological, phonological, lexical, or syntactic analysis.