How does a traditional blockchain handle competing blocks?

Traditional blockchains resolve competing blocks by picking one winner and discarding the rest as orphans. Each block in a standard chain has exactly one parent, forming a single linear sequence. When two blocks are produced at the same height — the same position in the chain — the network selects one and throws the other away. That discarded block is called an orphan, and all the work that went into creating it is wasted. Understanding this trade-off helps explain why protocols like Kaspa's GHOSTDAG, which keep parallel blocks instead of discarding them, represent a meaningful departure from the original blockchain model.