How does Kaspa's block structure differ from Bitcoin's?

Kaspa allows each block to point to multiple previous blocks, while Bitcoin allows blocks to point to only one. In Bitcoin, that single-parent rule means the chain is always a straight line — any block created at the same time as another gets discarded. Kaspa's multi-parent design lets parallel blocks coexist in a DAG, but that flexibility introduces an ordering problem: when blocks have multiple parents, the order between them cannot be determined by the DAG structure alone. Kaspa handles this with an additional Merkle Tree that standard single-parent blockchains never need. For a beginner, this is the core architectural trade-off that lets Kaspa keep blocks that Bitcoin would throw away.