1. A method of creating or modifying a hypertext document, comprising: (A) receiving, at one or more computer processors, natural language (NL) commands describing one or more of (i) content of the hypertext document, (ii) a layout of the hypertext document, or (iii) behavior of the hypertext document; (B) performing, at one or more computer processors, NL processing of the NL commands to determine one or more of (i) content to be included in the hypertext document, (ii) a layout for the hypertext document, or (iii) parameters corresponding to behavior of the hypertext document, wherein performing the NL processing includes: determining, at one or more computer processors, assumptions concerning (a) ambiguities associated with the NL commands and (b) information necessary for creating the hypertext document not specified by the NL commands, wherein the assumptions correspond to the one or more of (i) content to be included in the hypertext document, (ii) the layout for the hypertext document, or (iii) the parameters corresponding to behavior of the hypertext document; and generating, at one or more computer processors, hypertext document code or data for displaying the hypertext document, wherein generating the hypertext document code or data is based on the NL processing of the NL commands including the determined assumptions; and (C) analyzing, at one or more computer processors, existing hypertext document data; and (D) modifying, using one or more computer processors, the existing hypertext document data based on one or both of (i) the NL processing of the NL commands and (ii) the determined assumptions.