> a company on the stock exchange splitting into two companies No, that is not what's happening here: Bitcoin is a consensus network where consensus is achieve

> a company on the stock exchange splitting into two companies No, that is not what's happening here: Bitcoin is a consensus network where consensus is achieved essentially by mining sequence of blocks, which requires a huge amount of computational power. Each block have a relation with the previous block. Sometimes two or more blocks are mined almost at the same time (creating a fork), miners then choose one and keep mining as fast as they can. At some point one fork will be longer than the other/s, which is when consensus happen: miners abandon the shortest forks and keep mining on the largest one.