What is digital signing?
In simple terms, digitally signing a document is associating your personality with the document. When you sign a document, you use your private key to encrypt a digest of the document. Only you have access to the key, nobody else can use it. The signature created on a document is valid only for this document, if the document is changed, it will break the signature, and GenuineDoc will detect that. So, after signing, there exists an unbreakable linkage between you and the document, via your key and digital signature.