Summary: This article provides definitions and descriptions of the Java stack and heap.
I just read a couple of emails about the concepts of a Java stack and heap, and thinking that their descriptions weren't exactly right, I decided to do a little research. There's no better source than the source, so directly from Sun's Java website, here are definitions for the Java stack and Java heap.
Java stack definition
Here's the definition of a Java stack, with a few pieces removed for clarity: