Dark secret of blogging #2: Numbering is narrative.

Take a moment to peruse PopURLs – one of my favorite snapshots of the Internet zeitgeist – and you’ll notice a recurring pattern – people love lists. The words “top 10″ or “5 best” or “3 most” just seem to hit some sort of primal switch in our brains, triggering us to devour and redistribute content.

Obviously the Web didn’t invent the top-10 list, but the popularity of this story form in this medium is definitely worth some rumination. First, however, one key point – a numbered list is a story form. It’s a way of shaping a narrative that has just as much legitimacy as a Q&A, a long-form feature, an inverted pyramid, or any other storytelling technique a writer might draw on.

I tend to think the most important thing to understand about the popularity of lists online is not that every blog post should be a list, but that lists reveal some of the implicit attributes of successful Web content that are worth keeping in mind no matter which story form you choose. To wit:

Lists promise comprehensiveness.

A top 10 countdown suggests that you’ve surveyed a wide territory and brought back its 10 most sparkling gems. When we read things, we don’t typically quantify how many discrete insights we expect to encounter. We might even approach information expecting a point – a single golden takeaway to be treasured and put to use. Given this expectation, 10 promised insights (!) seems extraordinarily generous.

Lists promise limits.

At the same time as lists suggest breadth and robustness, they also convey selection. You aren’t just dumping everything on us, you’ve winnowed it down to 10 elements or 6 or even 3. The subtle message: “This is all you need to know.” In the age of information overload, that’s a huge selling point.

Lists promise hierarchy.

The Web loves hierarchy. Our information diets are glutted with streams of info all given equal weight – emails and status updates and articles and links. In that environment, information given a clear, unequivocal, easy-to-parse structure stands out. You can read a list from beginning to end, or if you’re pressed for time, just savor the best bits. What’s not to love?

Lists connote authority.

To assert the selection of a top 10 is to assert ownership of a topic. On the Web, content lends authority as often as brand. A complete unknown with a top-10 list that rings true to its audience can command as much attention as an established expert in a field. (I see this as both a good thing and a bad thing.) But it means that lists are an efficient signal that you think you’ve got enough experience on a topic to condense it.

A numbered list isn’t the only way to send these signals, of course. Other popular story forms online exude many of these same attributes. For example, the “ultimate guide to everything you need to know about X” is another format that promises authority and completeness, and you’ll find these posts are very popular as well. If you can grok why these formats are so Web-friendly, you can tailor your stories and headlines to match the sensibility.