Please note that the content of this book mainly consists of articles that are available online from Wikipedia or other free sources. The academic mountain-building era in the Paleozoic is the summarizing plate tectonic designation of a series of worldwide, partially overlapping orogens during the formation of Laurussia, in the lead-up to the emergence of the last global supercontinent, Pangaea. This mountain-building process is divided into three sections. The terminology and chronology are largely inconsistent and confusing even for experts, as the underlying theory of plate tectonics, proposed by Alfred Wegener, has only been a general foundation of geology since the 1970s. The terms are often used carelessly, different spellings exist, and some terms from earlier concepts continue to persist.