As learned recently. Bitcoin was like a single entity before it was later separated into 2 separate block chains in 2017; the original Bitcoin and the Bitcoin cash. At the said time, the Bitcoin community tried to determine how it can improve it's networks ability to process more transactions at the same time. As at the time, Bitcoin could only process 1 megabyte of transaction at a time, which led to delays in transactions being processed.
During the process also known as the (hard fork), a proposal to increase the average block size in Bitcoin's block chain was rejected by the crypto currency's core development team. They rejected the change, despite the fact that high transaction fees made Bitcoin use as a medium for daily transactions unsustainable. The only one's that benefited from the high transaction fees were miners. At a later date a renegade group of developers and miners moved away and created their own crypto currency with variable block size. The hard fork between Bitcoin and Bitcoin cash was done in part to increase the processing limit from 1 megabyte to 8 megabytes