what is the difference between XSL and XSLT

[chelvis]

I have the wrox book Professional XSL. I was searching in the internet and came accross the box from wrox XSLT.

What is the main difference between XSL and XSLT?

[jkd]

XSL is the set of XPath, XSLT, and XSL:FO as far as I know.