The split originated from what was described as a "civil war" in two competing bitcoin cash camps. The first camp, supported by entrepreneur Roger Ver and Jihan Wu of Bitmain, promoted the software entitled Bitcoin ABC (short for Adjustable Blocksize Cap) which would maintain the block size at 32MB. The second camp led by Craig Steven Wright and billionaire Calvin Ayre put forth a competing software version Bitcoin SV, short for "Bitcoin Satoshi's Vision," that would increase the block size limit to 128MB.
Rising fees on the Bitcoin network contributed to a push by some in the community to create a hard fork to increase the blocksize. This push came to a head in July 2017 when some members of the bitcoin community including Roger Ver felt that adopting BIP 91 without increasing the block-size limit favored people who wanted to treat bitcoin as a digital investment rather than as a transactional currency. This push by some to increase the block size met a resistance. Since its inception up to July 2017, Bitcoin users had maintained a common set of rules for the cryptocurrency. Eventually, a group of bitcoin activists, investors, entrepreneurs, developers and largely China-based miners were unhappy with Bitcoin's proposed SegWit improvement plans meant to increase capacity and pushed forward alternative plans for a split which created Bitcoin Cash. The proposed split included a plan to increase the number of transactions its ledger can process by increasing the block size limit to eight megabytes.
EDA adjustments caused instabilities in mining difficulty of the Bitcoin Cash system, resulting in Bitcoin Cash being thousands of blocks ahead of Bitcoin. To address the problem with stability, a change of the Bitcoin Cash DAA was implemented and the EDA cancelled. The change took effect on 13 November 2017. After the change, the Bitcoin Cash DAA adjusts the mining difficulty after each block. To calculate the difficulty for a new block, the Bitcoin Cash DAA uses a moving window of last 144 blocks.
BCH is a cryptocurrency established as a result of the hard fork that took place to manage the scalability problem. Bitcoin Cash has a number of significant differences to Bitcoin: it is advertised as being faster and cheaper to use, the maximum block size is eight megabytes against one in previous Blockchain, and it has an emergency difficulty adjustment feature. Bitcoin Cash also uses 0-conf (or zero-conf) which allows for nearly instant transactions, meaning Bitcoin Cash transactions are almost always confirmed in the next block.
Bitcoin Cash (BCH) is hard fork (a community-activated update to the protocol or code) of Bitcoin that took effect on August 1st, 2017 that increased the block size to 8MB, to help the scale the underlying technology of Bitcoin.Nov 16th 2018: BCH was hard forked again and split into Bitcoin SV and Bitcoin ABC. Bitcoin ABC became the dominant chain and took over the BCH ticker as it had more hashpower and majority of the nodes in the network.
There are two factions of bitcoin supporters, that support large blocks or small blocks. The Bitcoin Cash faction favors the use of its currency as a medium of exchange for commerce while the Bitcoin-supporting faction view bitcoin's primary use as that of a store of value. Some Bitcoin supporters like to call Bitcoin Cash “Bcash,” “Btrash,” or simply a scam, while Bitcoin Cash advocates insist that their implementation is the pure form of Bitcoin.