Bitcoin Cash was a result of a hard fork from Bitcoin core in August 2017, and on 15 May 2018, it will fork again to update the consensus rules. The update includes various op code revisions but the biggest change is to accommodate 32MB block sizes.
Bitcoin core retains the original 1MB block size whereas Bitcoin Cash will continue to use an 8MB block size until the May 2018 fork is implemented. Satoshi Nakamoto secretly introduced a limit to the block size in the core software, fearing that the network would be subject to denial of service (DOS) attacks without it. In the early days of Bitcoin, it was much easier to implement changes as the software wasn’t analyzed by the community to the level it is today.
updates to code make the future.