What is Writing?

Legal Definition
Writing is a medium of human communication that represents language and emotion through the inscription or recording of signs and symbols. In most languages, writing is a complement to speech or spoken language. Writing is not a language but a form of technology that developed as tools developed with human society. Within a language system, writing relies on many of the same structures as speech, such as vocabulary, grammar and semantics, with the added dependency of a system of signs or symbols. The result of writing is generally called text, and the recipient of text is called a reader. Motivations for writing include publication, storytelling, correspondence and diary. Writing has been instrumental in keeping history, maintaining culture, dissemination of knowledge through the media and the formation of legal systems.

As human societies emerged, the development of writing was driven by pragmatic exigencies such as exchanging information, maintaining financial accounts, codifying laws and recording history. Around the 4th millennium BCE, the complexity of trade and administration in Mesopotamia outgrew human memory, and writing became a more dependable method of recording and presenting transactions in a permanent form. In both ancient Egypt and Mesoamerica writing may have evolved through calendrics and a political necessity for recording historical and environmental events.
-- Wikipedia
Legal Definition
The act of forming by the hand letters or characters of a particular kind on paper or other suitable substance, and artfully putting them together so as to co nvey ideas. It differs from printing, which is the formation of words on paper or other proper substance by means of a stamp. Sometimes by writing ii understood printing, and sometimes printing and writing mixed.

2. Many contracts are required to be in writing; all deeds for real estate must be in writing, for it cannot be conveyed by a contract not in writing, yet it is the constant practice to make deeds partly in printing, and partly in writing. Wills, except nuncupative wills, must begin writing, and signed by the testator; and nuncupative wills must be reduced to writing by the witnesses within a limited time after the testator's death.

3. Records, bonds, bills of exchange and many other engagements, must, from their nature, be made in writing, See Statue of Frauds; Language.
-- Bouviers Law Dictionary
Legal Definition
The expression of ideas by letters visible to the eye. Clason v. Bailey, 14 Johns. (N. Y.) 491. The giving an outward and objective form to a contract, will, etc., by means of letters or marks placed upon paper, parchment or other material substance. In the most general squse of the word, "writing" denotes a document, whether manuscript or printed, as opposed to mere spoken words. Writing is essential to the validity of certain contracts and other transactions. Sweet
-- Black's Law Dictionary