Walther PPK (Polizei Pistole Kurz - Short Police Pistol) is a shortened wersion of the Walter PP (polizei Pistole) and differs from it only in size (shorter barrel and grip). Walther PP was presented in 1929, PPK - in 1931 and quickly become wery popular among European police agencies and civilian shooters - both guns were reliable, easy to conceal (especially PPK), but of moderate power (esp. versions in .22LR, 6.35mm auto (.25ACP) and 7.65mm auto). During WW2 those guns were issued to german military police personnel, high military officers and other military personnel. In fact, PP and PPK were the worlds first successful DA autos. They were (and are) copied and still in production by bot the Crl Walther Sportwaffen gmbh. and other companies. technically, PP and PPK are blowback operated DA handguns. Both have chamber loaded indicator, external hammer, manual safety and out of battery safety. The manual safety is somewhat odd, because it has to be turned UP to be set to fire position, instead of common down direction. Both guns deserved good reputation during the decades of use. Especially popular they become as a James Bond (Agent 007) weapon (Walther PPK) in almost all novels and all but the most recent movies, when James Bond switched to more modern Walther pistol - a P99.