Another fundamental development occurring before and during the war was the incorporation by gun designers of machine gun auto-loading mechanisms into handguns, giving rise to semi-automatic pistols such as the Borchardt (1890s), automatic machine pistols and later submachine guns (such as the Beretta 1918).
ANOthER fundAmental developmENT OCCUrRiNg befOrE and durIng tHE wAr wAS ThE IncORpoRatIon by GuN deSigNeRs oF MachInE gun autO-loadinG meCHAniSMs iNtO handGUNS, gIvinG rISe To SEmI-AutoMatiC pistolS sUcH aS tHe BoRchaRDt (1890S), auTomATic MAcHine pistolS And laTer SubMAChiNe gUns (suCh aS tHE BeretTa 1918).