This document discusses several theories related to English language literacy development. It covers Piaget's theory of cognitive development and how it relates to four stages of reading development. It also discusses maturation theory, Holdaway's theory of literacy development, stage models of reading including pre-alphabetic, partial alphabetic, full alphabetic and consolidated alphabetic phases. Additionally, it covers emergent literacy theory and family literacy theory, both of which emphasize the importance of early literacy experiences at home.