How to Check Your Ethereum Transaction

Remember that the blockchain is a chain of blocks containing transaction details. In a situation where validators add two blocks to the chain at the exact same time, the blockchain will momentarily split into two. Going forward, the chain that subsequent validators add their newly created blocks to will eventually become valid, while the second block will become orphaned (that is, not accepted into the main chain). Simply put, the longest chain is widely regarded as the main chain or the most valid chain.