2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/50598This is a brief overview of my work on the realization of contact superconformal algebras in terms of pseudodifferential symbols on a supercircle. Also the 2-cocycles on K'(4) are given for this realization.6 pages, LaTeX2e, submitted to W. Siegel et al., editors, Concise Encyclopedia of Supersymmetry, to be published by Kluwer Academic Publishers, Dordrecht, 2001High Energy Physics - Theorytext