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A directed acyclic graph (DAG) is a probabilistic transaction scheme that allows for one to separate micro/macro transactions with different security domain tradeoffs in exchange for convenience. Z-DAG allows merchants to decide whether to accept or decline a DAG transaction based on their preference. A DAG can be compared with a tree which grows in several separate branches. It has an interesting structure similar to a tree where every transaction has to verify two prior transactions. This division in branches allows for a higher TPS than regular blockchain technology.