Bitcoin Cash (BCH)
There is no whitepaper for BCH.
Who is behind it?
I could not pin the development on one single person or team, a community of people mostly seems to drive the project. The one thing beeing for sure is that the chinese Bitcoin mining company ViaBTC played a major role in the sucessfull launch of the currency. They provided the much needed processing power in the beginning to give the project the credibility it needed to survive.
What technology is it based on?
To keep things short - BCH is an almost exact copy of BTC, with the only notable difference beeing a blocksize increase to 8MB instead of Bitcoin's original 1MB. The original chain was hard-forked on August 1st. 2017.
Does anybody really need it?
BTC's block size has always been 1MB. As transactions need to fit in the upcoming block to be processed sucessfully and with their amount vastly increasing from 2009 until today, the blocks got larger and larger until the maximum capacity of 1MB was reached. Transactions with low fees were rejected by the successfull miner and had to try their luck in the next block. A backlog started to build up, making the network extremely slow and transactions expensive. In 2016, it was clear that BTC desperatly needed a solution for this problem. Besides the group of die-hard-originalists (which did not want any changes to the block size at all), there were two groups left. One in favor of Bitcoin Improvement Proposal 141 (BIP141), the other one opposing it. BIP141 proposed the concept of the so called Segregated Witness, short SegWit, which would have effectively increased the block size to 1.4MB and allowed for almost countless, extremely fast transactions in the network. SegWit's main advantage would have been its existence as a soft-fork. (SegWit isn't part of this article, so I'll keep things short here)
The other group, opposing SegWit for a variety of reasons, decided to hard fork their own chain, with blackjack and hooke...ah no, I mean with a vastly increased block size, which would yield a similar end result.
Yada, yada, so do you need it?
Not all big players in BTC have implemented SegWit yet and therefore sending funds from one exchange to another can still take days and cost upwards of 25$. So, yes, I think BCH had it's place and will continue to do so until SegWit has been widely implemented on the original chain. If that happens, from a technological point of view, BCH is no different from thousands of other hard-forks of the original chain.
So is it shit?
I say no, it's not, at least not for now. At the time, BCH was the fastest solution the to gigantic problem of slow transactions and high fees. It had a clear reason to exist and while it's original creators probably made more than just some profit of it, it could very well also have died like similar projects earlier did, Bitcoin TX beeing one example.
No consensus on SegWit could be reached, an argument ensued, BCH was born. The only notable technological difference is a vastly increased block size of 8MB instead of 1MB.
On a scale from 1-10, I give Bitcoin Cash an 7. At the time, it was the direct solution to a problem that still exists today. When the last exchange and wallet have integrated SegWit, this number will drop to 2, though. At that point, BCH will only be one more BTC hard fork slowly fading into darkness, with no edge over its competitors besides it's very high market capitalisation.