5. The computer-based system of claim 4, wherein compliance with at least one of a legal requirement and a business practice comprises: a content block for a type of significant communication; and a protocol for manipulation of the content of such block.
4. A computer-based system for processing a document that is human readable and machine processable, comprising: a document type definition according to the standard generalized mark-up language standard, wherein the document type definition provides for compliance with at least one of a legal requirement and a business practice, and a signature algorithm, wherein a recipient of a signed portion of the document may verify one or more of the authenticity, the execution and the integrity of the portion without having access to the entire document.