What exactly is GUID? Why and where I should use it?

Question

What exactly is GUID? Why and where I should use it?
I\'ve seen references to GUID in a lot of places, and in wikipedia, but it is not very clear telling you where to

Answer 1

GUID = Global Unique IDentifier.

Use it when you want to uniquely identify something in a global context.

This generator can be handy.