Finally - after 41 years, from Diffie and Hellman's concept in 1976 through to real-life production usage in 2017, digital signatures are now in regular use: yes, penned signatures, wax seals and paper itself are finally taking a back-seat. And a big driver in making this a success is PDF.
But we need to look into the history of digital signatures and PDF technology and where they overlapped.
Back to the 70's
1976 - Diffie and Hellman theorized the concept of a digital signature which could help validate digital documents.
1977 - Rivest, Shamir, and Adleman created the first digital signature algorithm, known as the RSA algorithm, which was used to produce an early version of what we know today as the digital signature.
1994 - The US National Security Agency (NSA) introduced the Digital Signature Standards (DSS), which looked to create standards for authenticating electronic documents. The standards were so forward focused and in-depth that the US Government made the Digital Signature Standards the standards for electronic document authentication across the country of America.
2008 - ISO 32000-1:2008 was introduced by the International Organization for Standardization (ISO) which created the standards around PDF technology, focused on developers of this technology. Digital signatures played a big part in these standards which made it possible to push PDF technology as a must-have corporate document management system.
2014 - eIDAS, or electronic Identification, Authentication and Trust Services, introduced regulations within the EU to provide a safe process for organizations to conduct business electronically.
Thank you, Mr. Diffie and Mr. Hellman!
Through these standards, electronic PDF contracts are now held to the same legal standing as paper contracts, making doing business electronically more viable to organizations across the world. You can bet that all us PDF lovers are rapt that using digital or electronic signatures in PDFs is pretty much standard in apps now. After all, it's a big part of doing business in the global community that organizations have created.
OK, so you want to stamp your document. Maybe you need to give reviewers some advice about the document's status or sensitivity. This tip from author Ted Padova demonstrates how to add stamps with the Stamp Tool along with related comments.