Which character in William Shakespeare's "Hamlet" is Hamlet's most trusted friend?

There are more things in Heaven and Earth, Horatio, that are dreamt of in your philosophy.

"Alas, poor Yorick. I knew him, Horatio..."

Well, we all need someone to really listen to us in times of crisis, to act as a "sounding board". As long as we return the favour at a later date, then all is fair!

Hamlet is my favorite story from the Bard.