TITLE: how to use arxiv?
QUESTION [50 upvotes]: This is a soft question. How do people usually use arxiv to put their papers? At which stage does one usually put his/her paper/report there? Someone suggests me to submit a paper while putting it on arxiv. Is that the convention that people follow?
Thank you!
Anand

REPLY [10 votes]: Yet another way in which people could use arXiv is as a repository for material which otherwise cannot find a home in a journal.  Sometimes in the course of working on a project I wind up with some material which did not make it into the published article -- or perhaps some notes which record my growing understanding of articles already published by others -- which look like they could be useful to the community as expository or supplemental information, but which in my opinion are not otherwise significant enough to warrant submitting to a journal.  I have sometimes wondered whether it would be appropriate to post such material on the arXiv.  (I have not done so yet.)  For that matter, I wonder whether others have done this very thing.  
One drawback of this use of the arXiv is that everyone knows that most arXiv articles have not been peer-reviewed at the time of first posting, so they must be taken with a grain of salt. If an article is never published in a journal, you must read the arXiv article with a more critical eye.  But as I said, I do believe that there exist some notes that are perhaps worth sharing but not worth wasting the effort to peer review.