Blockchain impacts transparency in transactions by providing a decentralized and immutable ledger that records all transactions securely. Every entry in a blockchain is time-stamped and linked to the previous entry, creating a chain that is visible to all participants. This aspect ensures that all parties can audit transactions at any time, fostering trust among users. Moreover, the transparency of blockchain reduces the potential for fraud and errors, as altering any data would require consensus from the majority of the network. This level of transparency is crucial for applications in finance, supply chain, and beyond.