If you want to share knowledge, you need to describe a problem where the knowledge would be useful in the form of a question that would be on topic for the site. That's blogging, Q&A style. The question should be just like any other good question on the site, keep it focused and to the point. You can elaborate as much as you like in the answer. Take care, however, to make the question constructive and narrow. Overly broad or subjective questions will still be closed even if the accompanying answer is spectacular.
You'll see a check box:
That will expand an editor for your 'answer', which in this case would be the article you wrote perhaps modified a bit to fit the context of the question as well as it can. Your answer will be posted at the same time your question is.
Stack Overflow doesn't have a community blog in the sense that other sites in the network do.
blog.stackoverflow.com used to be the place where the SO team would blog about the site and the Stack Exchange network, later moved to
blog.stackexchange.com, but so many people were used to the old one that it was left in place to avoid breakage and preserve history. Not enough interest surfaced to really explore a work around for this.
I've been thinking of ways that we can expand our existing tag wiki system prior to writing a concrete proposal. These sorts of 'gists' have crossed my mind, but they'd have to:
- Be peer reviewed and vetted, like all other information on the site
- Not detract from the Q&A nature of the site
... which leaves it rather stuck on 'not detract from the Q&A nature of the site'. So, until (and if) we work out where we're going to blog and how it will be organized, your best bet is to just ask and answer your own question.
As for a place to collaborate prior to posting, each site has a 'chat' link in the header, which was specifically designed to facilitate real time collaboration.