Chris Pearson is one of the premier WordPress developers. He understands WordPress as well as anyone- and he has a post on his site that everyone should read, here is an excerpt:
categories are a powerful tool that bloggers can use to exercise precise control over content in a dynamic environment.
Unfortunately, the true power of categorized content has been masked by the one size fits all implementation you see everywhere on the Web—the proverbial long, ugly list of category links now appearing on a blog near you.
As luck would have it, that awful category list also turns out to be a very poor presentational strategy for your site… But why?
Why Your Category List Isn’t Doing You Any Favors
By giving users a list of categories to browse on your site, you are creating a psychological conundrum that usually leaves them with a severe case of analysis paralysis. This is a condition where users, when presented with too many options, end up selecting nothing at all.
Being presented with more choices, even good ones, can hinder effective action. In one study, doctors couldn’t make a decision when a second promising drug showed up.
— Fast Company, November 2007
Counter-intuitive? Maybe. Human nature? Absolutely.
Whether you’re selling products, writing copy, or designing interfaces, you can benefit from playing into basic human psychology. And interestingly, with Website categories, accommodating natural human behavior also turns out to be an excellent SEO strategy
Automated SEO and Content Management with Categories
At first glance, it seems convenient that WordPress automatically creates category pages, tag pages, and just about every other type of page you can imagine1. Dig a little deeper, though, and you’ll find that this form of page bloat is a remarkably poor site-building practice—it’s a condition that should be avoided whenever possible.
As far as blogs are concerned, categories are the single biggest contributor to both page bloat and link dilution, two of the most abominable SEO sins. Ironically, when used properly, these same categories hold the key to efficient, automated site optimization and content management…
The difference, of course, is all in how you use them. Armed with a bit of knowledge and a few lines of code, you’ll be able to use categories to:
display content however you like, wherever you like
link directly to interior pages—not to interstitial “bloat†pages like monthly archives or category archives
provide your users with a smarter, more intuitive way to browse content that may be of interest to them… read the rest at:
What Every Blogger Needs to Know About Categories — Pearsonified.
I like to think of Categories as the table of contents to your site (in this metaphor- tags would be the index)- they are there to help a reader find what they are most interested in, and to group posts of a similar nature.
They are also a powerful tool to refresh old content in Google’s eyes- by collecting old posts with new posts Google sees the category as a new mix of keywords every time you add content to a category.
We can also use categories to present information in different places or in different ways if we want, but for the most part, they are a critical component of navigation. Read Chris’s whole post to learn more.
Yes, I know you aren’t Apple, or have a product like the iPhone, but if someone wants your product, they’ll turn to Google. This short article summing up what kind of numbers a hot product can generate and how Google is the only one that matters:
MacNN | iPhone generates 7m US searches in April
the iPhone generated huge traffic for internet search engines in April. ComScore, which provides market research for advertisers, says 1.3 million Americans conducted 6.9 million iPhone-related searches in April. The word “iPhone†was the most popular term, with nearly 1.5 million searches, followed by “iPhone 2.0†and “iPhone 3G.†The vast majority of those seaches — 88.4 percent — went to Google, Yahoo got about 7 percent, with MSN getting less than 3 percent.Those searches generated a lot of traffic for Apple, which attracted 17.5 percent of search click-thrus. Of that number, about 17 percent were the result of “paid†searches, the rest were “organic” searches. Google’s You Tube and various blogger sites garnered about 9 percent of the total click-thrus, followed by NetShelter Technology Media at about 8.5 percent. NetShelter owns several iPhone-specific sites. The data were collected using comScore Marketer software.
“Search is frequently a harbinger of purchase intent,†said Dan Lackner, Senior VP of comScore. “The increase in volume of iPhone searches demonstrates just how heavy that interest has been for the next generation of Apple’s popular phone — even when its existence was still just a rumor.”
As if it needs repeating: “88.4 percent — went to Google, Yahoo got about 7 percent, with MSN getting less than 3 percent.” Optimizing for Google isn’t optional.
Someone said on the hackers forum: “The analogy I use is that Categories are like a book’s table of contents, and Tags like its index.”
However, be aware that categories that are actual search terms are very strong Google magnets.
So, instead of using a category “lines we carry” think about “High Performance Motorcycles in Dayton OH” and then use tags to highlight the brands and product names.
Tags are ways to identify the keywords or concepts in each post- categories group the posts in ways that make sense for others. Lately, Google has started dinging sites for putting a single post in more than three categories (which is too bad)- so think carefully about your choice of categories.