There are different versions of concept mapping. The purpose of this paper is to compare some of them and to explicate the main differences. Proper concept mapping methods include all methods of knowledge graphic presentation that are clearly based on the seminal writings of Novak and his research group from 1981 to 2002. Some writers may use the term concept mapping, although one of the most basic requirements is not fulfilled: No meaningful propositions are produced out of linked concepts. Sometimes no links at all are present, only concepts spread in a conceptual space. In "the Novakian Standard Concept Mapping Format" there are some unnecessarily complex rules. Critical reflection on alternative ideas about concept mapping may suggest alternative and better ideas in the future.

Varieties of concept mapping approaches have recently been outlined by Âhlberg (2004). According to Âhlberg, the only mapping techniques that deserve the label concept mapping are those that are both clearly based on the seminal writings of Novak and his research group from 1981 to 2002 and that fulfill the basic requirement that meaningful propositions may be produced out of linked concepts. He points out that in following Novak´s standards, there are some unnecessarily complex rules, which may be overcome in the future. For example, he suggests that improved concept maps may also include whole phrases to signify the meaning of a concept instead of short labels, that multimedia resources may be connected to maps, and that, in some cases, numbers may be included showing the order in which the propositions should be read.