Concept maps are resources for the representation and construction of knowledge. They allow the showing, through concepts and relationships, how knowledge about a subject is organized. Technological advances have boosted the development of technological approaches that help the automatic construction of a map, in order to facilitate and provide the benefits of that resource more broadly. Because of the need to better identify and analyze the functionalities and characteristics of the technological approaches inserted in this context, we developed a categorization based on bibliographic review of the area between 1994 and 2015. This work aims to present the proposed categorization and the main features and limitations of the approaches studied observing this categorization.