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.
“The arguments have devolved over three or four years of bitter debate, the principles are real and they are important to preserve, but a lot of the drama has nothing to do with principles anymore. A lot of this debate is now more about hurt feelings. It’s about bruised egos. It’s about things that were said that can’t be unsaid, insults that were exchanged, and personalities and ego.”
Both Bitcoin as well as Bitcoin Cash use a proof-of-work algorithm to timestamp every new block. The proof of work algorithm used is the same in both cases. It can be described as a partial inversion of a hash function. Additionally, both Bitcoin and Bitcoin Cash target a new block to be generated every ten minutes on average. The time needed to calculate a new block is influenced by a parameter called the mining difficulty. If the total amount of mining power increases, an increase of the mining difficulty can keep the block time roughly constant. Vice versa, if the mining power decreases, a decrease of the mining difficulty can keep the block time roughly constant.
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.