The question of how children come to understand how the orthography of English works has been a central issue in reading research for well over 100 years. Reading educators have developed what they believe to be helpful conclusions and explanations for the development of orthographic word knowledge as it relates to reading, writing, and instruction. Their position is that children's invented spelling, or spelling errors, are indicative of their tacit understanding of the alphabetic principles of written language--the knowledge that would be used to spell or recognize a nonsense word. Reading educators have become convinced that a centralized word knowledge is used for both spelling and word recognition. Further, reading educators believe that the development of this word knowledge is consistently stage-like across all children but that the rate and ease of its progression varies with each individual. Finally, reading educators contend that instruction is all important in learning to read, but that it can only affect the ease with which children learn to read rather than the way they learn. Children learn to read with varying degrees of ease and speed depending upon the congruence between what the teacher presents and what the mind requires. (Two figures are included; 34 references are attached.) (RS)