First, I'd like to thank everyone for their suggestions/ 
recommendations.  I spent some time with gnuplot and it became  
evident that it was both too complex and major overkill for what I'm  
trying to do.  Basically, I would like to generate simple graphs  
(usually scatter plot) and display them as an image in a web page.   
The actual graphing would ideally be similar to the type MS Excel  
puts out if possible.

I'm sorry for not specifying what I was looking for clearly before.   
Any further suggestions on what libraries might be able to do this  
would be appreciated.

-Thanks
Shalev