Written Language refers to communication in its written form - specifically skills contributing  to and including reading and writing.  There is evidence that we are "hard-wired" for oral language; speaking and listening skills are most often acquired naturally by young children without the need for systematic, explicit teaching.  Language in its written form, however, is a process that is "superimposed" on our innate oral language rules and must be explicitly taught.  Many languages continue to exist that do not have a written form.
 

As literacy skills emerge, oral and written language are closely intertwined.  School-based therapy to address oral language delays and disorders is often conducted in conjunction with reading and writing activities, as the interaction between the two forms of communication is well-documented.  For example, increased awareness and understanding of how sounds and letters relate to one another can have reciprocal effects on a child's articulation skills.  As children develop awareness of print and begin to read and write, much of their new vocabulary is acquired through reading.  Written language is more complex than spoken language, so that children who read more develop more sophisticated language skills in all domains.
 

Links on these pages (above) will lead you to definitions useful in understanding literacy development, as well as additional information regarding literacy, spelling, dyslexia, and basic writing skills.