Deconstructivism is a postmodern architectural movement which appeared in the 1980s. It gives the impression of the fragmentation of the constructed building, commonly characterised by an absence of obvious harmony, continuity, or symmetry. Its name is a portmanteau of Constructivism and "Deconstruction", a form of semiotic analysis developed by the French philosopher Jacques Derrida. Architects whose work is often described as deconstructivist include Zaha Hadid, Peter Eisenman, Frank Gehry, Rem Koolhaas, Daniel Libeskind, Bernard Tschumi, and Coop Himmelb(l)au.