Whats the difference between a Pandemic and an Epidemic?

So I am sure you have thought this over the last week or so with the rise of the Swine Flu Pandemic. What is the difference between a Pandemic and an Epidemic? I know I certainly wondered such. Well, here is your answer.

An Epidemic affects a region or a large part of a populated area while a Pandemic is worldwide. The last Pandemic flu was the Hong Kong Flu Pandemic of 1968 in which 39,000 died in the United States and nearly 1 million died worldwide.

So far the Swine Flu has killed about 150 in Mexico and is spreading with cases turning up all across the globe. It would be quite scary if the Swine Flu Pandemic reaches anywhere near the proportions of the Hong Kong Flu Pandemic. If so we are at the very beginning of the Pandemic currently.