Writer, [ry-ter] - noun:

One who practices a scribbling of language onto paper, or lately, digital form. In some cases, the content of said scribbling is of great value, if not of some utility, though for the most part it is neither. In the case of digital writing, especially that of blogs, a secondary writing known as comments, takes up the matter of precisely what value shall be assigned to a particular piece of writing. The comments are not writing in and of themselves, but they do determine that someone who has encountered the original writing has taken note of it to the extent that it merits an additional round of scribbling.

The toilet-stall bard Nickerson has composed a limerick describing the commitment required for quality writing:

A scribe with an intellect fine
Supposed he would write all the time
He picked up a pen
But just wrote now and then
While sipping a glass of red wine