Eurodollar Futures liability, conceptual, understand, long

hw0799

I'm having a really hard time trying to understand this contract. From my understanding, it's deliverable obligation is a 90 day t-bill which is somehow indexed to LIBOR? Can someone please help me understand this intrument.

So:

If you are long a Eurodollar contract what does that mean?
How is it priced at initation? (Not looking for maths just a rough conceptual explanation)
If you were hedging a floating LIBOR liability why would you do this by going long a Eurodollar futures contract?