I am speechless but not surprised.
He died of his Alzheimers disease surrounded by his family and pets (although pets ARE family). Originally he planned to commit assisted suicide, but he didn't.
His publisher, Transworld issued a statement today:

"It is with immeasurable sadness that we announce that author Sir Terry Pratchett has died.
The world has lost one of its brightest, sharpest minds. Rest in peace Sir Terry Pratchett."

RIP my favorite author.

Felt some kind of helplessness when found out.

Is my favourite fantasy author too.

He will never truly leave this world as long as we read his books and speak his name

One of the must gut wrenching things I ever read was the tweets announcing Terry's death.  His willingness to live and even was willing to die on his terms is a huge inspiration to me