Digital Signatures (DSC) are electronic signatures used to authenticate the identity of the sender of a message or the signer of a document. They provide a high level of security and integrity to digital documents and transactions by ensuring that the content has not been altered or tampered with during transmission. DSCs use cryptographic algorithms to create a unique digital fingerprint for each document or message, which is encrypted and attached to the digital file. This digital fingerprint, along with the signer's public key and certificate, is used to verify the authenticity and integrity of the document or message. DSCs are issued by certified authorities known as Certifying Authorities (CAs) after verifying the identity of the applicant through a stringent process. They are widely used in various applications, including online transactions, electronic contracts, e-filing of tax returns, digital signing of invoices, and secure communication between parties. DSCs come in different classes and types, each offering different levels of security and functionality to meet the diverse needs of users.