1. A method of mapping and transforming information in a first format to information in an HTML format, comprising: inputting into a map editor a structural description of a first system having the first format, the first format having a set of structural descriptive elements; inputting into the map editor a description of a second system that communicates over a protocol having the HTML format; displaying in a graphical user interface, a first list of structural descriptive elements in the first format and a second list of descriptive elements in the HTML format, the second list including a null-assigned element; inputting into the map editor from the graphical user interface, by a user, user operations that define an associative mapping from the first format to the HTML format, the user operations including at least selecting a first element in the first list and selecting a second element in the second list, the first element being mapped to the second element in the second list, wherein if the second element is the null-assigned element, the first element is not mapped to any element in the HTML format; outputting from the map editor the mapping from the first format to the HTML format, based on the inputting from the second system, the first system, and the graphical user interface into the map editor, the mapping being determined without use of a parse tree; and transforming a first document having the first format into a second document having the HTML format based on said mapping.