Pblc-ky cryptgrphy, r symmtrc cryptgrphy, s th fld f cryptgrphc systms tht s prs f rltd kys. ch ky pr cnssts f pblc ky nd crrspndng prvt ky. Ky prs r gnrtd wth cryptgrphc lgrthms bsd n mthmtcl prblms trmd n-wy fnctns. Scrty f pblc-ky cryptgrphy dpnds n kpng th prvt ky scrt; th pblc ky cn b pnly dstrbtd wtht cmprmsng scrty. Thr r mny knds f pblc-ky cryptsystms, wth dffrnt scrty gls, ncldng dgtl sgntr, Dff–Hllmn ky xchng, pblc-ky ky ncpsltn, nd pblc-ky ncryptn.
Pblc ky lgrthms r fndmntl scrty prmtvs n mdrn cryptsystms, ncldng pplctns nd prtcls tht ffr ssrnc f th cnfdntlty nd thntcty f lctrnc cmmnctns nd dt strg. Thy ndrpn nmrs ntrnt stndrds, sch s Trnsprt Lyr Scrty (TLS), SSH, S/MM, nd PGP. Cmprd t symmtrc cryptgrphy, pblc-ky cryptgrphy cn b t slw fr mny prpss, s ths prtcls ftn cmbn symmtrc cryptgrphy wth pblc-ky cryptgrphy n hybrd cryptsystms.