Statistics - difference between joint distribution and joint density?

[Kuma]

Homework Statement

This is just a general question about understanding.

What is the difference between a joint distribution functions vs. a joint density function.

Homework Equations

The Attempt at a Solution

Are joint density functions basically the joint distributions of continuous Random variables and joint distribution pertain to discrete random variables?

 

[lanedance]

see bleow
http://en.wikipedia.org/wiki/Joint_probability_distribution

personally i would loosely call them the same thing, probability density function is usually used for continuous RVs, whilst probability mass function is used for discrete RVs and both are examples of distributions