1. THE KEY: The number of visitors to your Hubs
2. Of the visitors to your Hubs, the relative proportion of those from search engines (Google, Yahoo, MSN, AOL, etc.)-the more from search engines, the more likely they'll click on ads and/or buy
3. The number of Hubs you write (especially if you group similar Hubs together)-the more, the better
4. The number of links to your Hubs from reputable (i.e. not junk) sites-again, the more, the better
5. The number of links to your Hubs from blogs and/or homepages-you guessed it! The more, the better
6. The number of links to your Hubs in your public signature in your discussion forum profile-By now you've caught on to the pattern

In fact, the more you increase 3, 4, 5, and 6, generally the more you'll increase 1 and 2. And an increase of visitors, especially visitors from search engines, means an increase in your AdSense, Amazon and Commission Junction (eBay) accounts.

There's a term for those links in 4, 5 and 6 above - backlinks. They have some value from people seeing them on those pages, and clicking on the links to your Hubs. That's called direct traffic. Nothing to sneeze at, and definitely helpful.

But, the real value of backlinks is that they're considered a thumbs-up by Google and Yahoo. The search engines will take a look at your Hubs (in a process called "spidering" or "crawling") shortly after you publish them. They'll take a look at your Title, and the content of your Hub, to get an idea about the topic. However, there might be hundreds, if not thousands or even millions, of other Webpages out there on the exact same subject. If someone goes to Google and types in "treo 650", why should Google list your Hub on the Treo 650 more prominently than the almost 3-million other pages out there on the same thing? Google wants to present the best quality pages first, but how does it know? There are no human judges rating the quality of the trillions of pages out there.

There are a few things that the search engines look at to estimate quality. First, it looks at the site that the page is on. Fortunately, on HubPages, we have thousands upon thousands of high-quality pages posted, so Google "trusts" our site (hubpages.com). That's an immediate boost to every new Hub that gets published on the site.

Second, it will look at backlinks. If your Hub has 10 backlinks (= 10 thumbs-up from people who think your Hub is worthy of a link to it), that will be a much higher measure of quality than a page that only has 3 backlinks to it, or none at all. Especially useful are links from sites that Google thinks are high-quality-i.e. a backlink from a popular, widely-read blog counts more than a backlink from your cousin Larry's blog that he updates once every 2 months. But even a backlink from Larry's blog is better than nothing.