According to their “about” page

Issuu turns your documents into beautiful online publications. Publish to an audience of millions and get your message across to anyone, anywhere. It only takes a minute and it’s free.

So you take your word documents, graphics, pdfs or what-have-you and upload them to Issu.  It then creates a web-based “magazine” that functions and flows like a professional magazine.  The proof is certainly in the pudding – they have a great showcase page of professional and amateur magazines and manuals.

My personal favorite is the online “guide” for soon to be released favo.  Check it out by visiting the favo website and clicking on “more info” (its a flash pop out otherwise I’d direct link you).  This is an incredibly useful and attractive way to debut a product or create a “manual.”

Hopefully Issuu will stick around and brands of any size can take advantage of this great tool.  There’s something powerful in how attractive the end result is, and is something you SHOULD be using to engage your audience.