Colt M1911A1 aka Colt Government Model. Its variants and copies are easilly recognizable and nearly all of them are Single Action Automatics. The only exception I am aware of is some models of the Canadian Paraordinance pistols.
Browning Hi-power. One of the most widely produced handguns of all time. A Single Action Automatic.
Colt Peacemaker. A Single Action revolver. Basic design is used for some modern weapons such as the Ruger Blackhawk.
Beretta M92. A Double Action Automatic. Standard handgun of the US army and widely used by other armies, police forces and individuals.
A SIG P226. A Double Action Automatic. Like many modern pistols it looks a lot like the Browning High Power. Note position of the magazine eject button at the base of the trigger guard on this and the Beretta. The Browning and M1911A1 have ejects in the same place.
Walther P38. Double Action Automatic. Has a heel mounted magazine release.
Walther PPK. Double Action Automatic. Heel mounted magazine release. Many similar weapons exist, including the Russian Makarov pistol.
Smith and Wesson Model 10. Typical of a Double Action Revolver.
A Glock pistol. A popular Double Action Only Automatic design. Note that it does not have an external hammer!
Taurus Revolver. An example of a hammerless Double Action Only Revolver.