Hi Ron,
You can't actually use Worksheets for charts. Chart-type sheet objects are totally distinct from Worksheet-type sheet objects. However, worksheets can include imbedded OLE objects, including Chart objects. The advantage of embedding a Chart on a Worksheet is that you can see the data the chart is graphing, and you can also put multiple charts on one worksheet. On the other hand the Chart sheet has the advantage of keeping the chart separate from its data--for example when you don't want to be distracted by viewing the data, or want the capability of printing just the chart and not the worksheet containing the data. The Chart sheet provides a much "cleaner" printed copy of the chart.
I find myself using embedded charts most of the time. But there are times I am glad the option to have them be separate sheets is available.
I hope this helps.
Damon