Once you've got the hang of creating a logical flow of your information creating Excel Charts is the next skill. If your information is important enough to track, chances are you are going to want to visualize it or, be able to present it to someone else in a meaningful way. Charts are the answer.
Some terms used in chart creation are series, data range, and axis labels. Series is quite simply a category of the information. If we are comparing expenses between 2007 and 2008, the year itself 2007 and 2008 denote your series. The monthly expense, or values, represent your data range. The months themselves would be considered the axis labels, they are required to add meaning to the information. As you can see from the screen shot below, without the months labeled across the axis, we would have a hard time understanding this information.
In my Basic Excel Charts video I used Microsoft Office 2003, 2007 uses the same terms, and functionality. The 2007 version has a much more visually orientated tool bar, the chart functions are available from the Insert tab.