The primary advantage of using a digital signature in documents is the enhancement of security and authenticity. Digital signatures utilize cryptographic algorithms to provide a unique identifier for the signer, ensuring the integrity of the document and verifying that it has not been altered post-signing. This technology also simplifies the process of verifying identities and can streamline transactions, especially in legal and financial agreements. Additionally, digital signatures contribute to a more efficient workflow by reducing the need for physical signatures and enhancing overall trust in electronic communications.