Adsense channels are a way to track your Adsense performance. There are two different types of channels - Custom Channels and URL Channels.

Custom channels allow you to track ad units. You'll only be able to use custom channels on your own domain and not on a revenue sharing site such as Hubpages. With custom channels you can track the performance of different ad units and determine whether particular sizes, colors and positions work better than a different, size, color and position.

URL channels allow you to track adsense performance at either the page or domain level. If you are a Hub author, these are the channels you will want to set up. You can either set up one channel for all of your hubs, or you can set up a separate channel for each hub. The latter is the best way to get an idea of which hubs are performing well, but there is a limitation to keep in mind. You can only have a maximum of 200 channels.

Once you log into Google Adsense, you want to click on the tab "Adsense Set-Up" at the top of the page, and then click on "Channels".

On the Channels page click on "URL Channels" and then click "+Add New URL Channels".

Then you can just start entering your Hubpage (or other website) urls in the box. If you want to just track all of your hubs as a single entity, the only thing you need to enter is hubpages.com and then click the button marked "Add channel". If you're going to add each Hub separately, then grab all of your hubpage urls and enter them in a batch or singly. Do not use your trackers. You want the raw url here.

And that's it. Now each time you log into your Adsense account, you can select "top channels" from the Reports menu and it will show you your top performing pages. You can also select "View All Adsense for Content channels" to get a performance overview of every page you are tracking.