Concept maps are a more complex version of mind maps. They place an emphasis on identifying the relationships between topics. Additionally, a node in a concept map can have several parents (whereas a node in a mind map will have just one).
Definition: A concept map is a graph in which nodes represent concepts and are related through labeled, directed edges that illustrate relationships between them
Concept map of Cell : The unit of lifeConcept map of Sexual Reproduction In Flowering Plants.