What is it? How is it different from BTC?
Bitcoin Cash Born: August 1, 2017
Was created on BTC Block #478558 -- block #478559 being its first block for Bitcoin Cash.
It was created as part of BIP91 (Bitcoin Improvement Proposal #91) and BIP148 (Bitcoin Improvement Proposal #148)
Notable names involved with Bitcoin Cash:
Roger Ver:Official Twitter
Calvin Ayre:Official Twitter
Bitcoin Cash Wiki
Bitcoin Cash FAQ
Bitcoin Cash has a blocksize of 8mb vs Bitcoin blocksize of 1mb (it holds more transactions per block).
It is mined the same way as Bitcoin (SHA-256 ASIC)
It is forked (derived from) from the original Bitcoin code.
Any address containing an amount of BTC during the fork received an equivalent amount of BCC/BCH.
It aimed at improving transaction cost and changing difficulty to improve transaction times.
It does not and will not use Segwit.
Hope this helps clarify some of the confusion with what exactly the difference between the two similarly named cryptocurrencies is.