In blockchain networks, transaction signing is crucial as it provides cryptographic proof that the sender of a transaction has authorized the transfer of assets. When a user initiates a transaction, their wallet uses their private key to generate a digital signature. This signature acts as a unique identifier that ties the transaction to the sender’s public key, confirming ownership and permission to perform the transaction. The signed transaction is then broadcast to the network, where it is validated and added to the blockchain by miners or validators. Without signing, transactions can be manipulated, leading to issues such as double-spending.