What is Bitcoin?
Bitcoin is a cryptocurrency, which was 1st introduced October 31st 2008,
by an unidentified programmer / group of programmers, although many have come forth and tried to claim credit.
What is the Bitcoin Difficulty at now?
Take a look at Bitcoinwisdom's Difficulty chart
What is the current Bitcoin reward per block?
This bitcoin.it wiki page on Controlled Supply Information
What is Bitcoin Cash?
Bitcoin Cash ( BCH ) is a version of Bitcoin after the fork occurred