What are the three most important functions that Digital Signatures perform?

Confidentiality is typically provided by encryption, not directly by digital signatures, which focus on integrity, authentication, and nonrepudiation.

Digital signatures use cryptography to verify the integrity of data (ensuring it hasn't been altered), authenticate the identity of the signatory (proving who sent it), and provide nonrepudiation (preventing the signatory from denying they signed it). These three elements are foundational to the trustworthiness of digital communications and transactions.

Authorization is about granting permissions to access resources and is not a direct function of a digital signature itself, though authenticated identity from a signature might precede authorization.

Detection (of tampering) is related to integrity, and accountability is covered by nonrepudiation, but authorization is not a direct function.