A digital signature or ID is more commonly known as a digital certificate. Digital IDs help validate your identity, and they can be used to sign important documents including PowerPoint presentations. Digital certificates are typically issued by a Certificate Authority (CA), which is a trusted third-party entity that issues these certificates for use by other parties. You can purchase a digital certificate from many commercial third-party certificate authorities or obtain a free digital certificate. There are many institutions, governments, and corporations that can also issue their own digital certificates.
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