A blockchain is an ordered list of transactions grouped into blocks, each linked to the previous by a hash. Copies of the chain are stored on many nodes, making silent tampering expensive.
Consensus rules (proof-of-work, proof-of-stake, and others) decide which block is canonical when validators disagree.
Once buried under enough confirmations, reversing a payment requires overwhelming the network — treat outbound transfers as final.
Public explorers (Etherscan, Tronscan, Mempool.space, etc.) let anyone audit a address history using the transaction hash Plume shows in deposit history.