Writing a Book

What does it mean to write a book?  I've just seen the movie, 'Pawn Sacrifice,' about Bobby Fischer and it reminds me of the place of knowledge and truth in human existence.  These things ought not be taken for granted and ought to be critically examined. Books and the process of writing one, I think are a way into the search for knowledge and truth.  What is knowledge?  What is truth?  Knowledge is the content of mind and it is the object of mind to get knowledge.  Truth is the outcome of the verification of knowledge.  Is there ultimate truth?  Of course there is!  It's God's knowledge.