Writing (portion 1)

Writing.

What is this exactly?
Can I get a text book definition please?
Ok:
"writ·ing
[rahy-ting]

–noun
1. the act of a person or thing that writes.
2. written form: to commit one's thoughts to writing.
3. that which is written; characters or matter written with a pen or the like: His writing is illegible.
4. such characters or matter with respect to style, kind, quality, etc.
5. an inscription.
6. a letter.
7. any written or printed paper, as a document or deed.
8. literary or musical style, form, quality, technique, etc.: Her writing is stilted.
9. a literary composition or production.
10. the profession of a writer: He turned to writing at an early age.
11. the Writings, Hagiographa.
—Idiom
12. writing on the wall. handwriting ( def. 4 )"
-- Dictionary.com

"2. written form: to commit one's thoughts to writing." -- It speaks to me.