API's used for charting

For those of you who are developers, could you recommend an API that is commonly used to display information via a chart.

I find that a lot of financial tools have a similar look and feel to the charts, for the most part do these software packages display this information using custom api's or are there some frequently used products available?

Thanks,

Dave

 

Anyone?

 

This one is freeware.

http://www.rmchart.com/

http://www.rmchart.com/rmc/gallery1.htm

 

For Java, jfreechart is widely used and quite good.

http://www.jfree.org/