The Wikipedia article on plate tectonics, consulted for its cited history section (Wegener 1912, seafloor-spreading evidence published 1959 to 1963, the theory defined in papers between 1965 and 1967) and its plain-language statement of the divergent, convergent and transform boundary types. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/