The digital signature is based on so-called asymmetric encryption. It is also known as a public key procedure and uses a public and a private (secret) key. The private key is used to generate the digital signature, while the public key is used to verify the authenticity of the signature.
Among the various types of digital signatures, the so-called qualified electronic signature is the only form of electronic signature that is legally equivalent to a handwritten signature (Art. 14 2bis OR / Art. 25 (2) eiDAS). In contrast to a simple (e.g. Adobe Sign) or advanced signature, it is based on a qualified certificate issued by a recognised trust service Provider.