Ruger is the name of the company that made the pistol. .380 ACP is the cartridge size. ACP stands for Automatic Colt Pistol- part of the cartridge name, as some of the first of the .380 cartridges were made for use in Colt pistols..
.380 ACP means .380 Caliber, Automatic Colt Pistol. Often shortened to 380 auto. In other parts of the world, the 380 ACP is called a "9mm short" (or Kurtz, Corto other languages for "short."). So yes.
A Colt Model M (also referred to by collectors as a Model 1908 Pocket Hammerless) in .380 ACP serial number 38366 was manufactured in 1920. For more information on this and other pre-WWII Colt firearms, visit http://www.coltautos.com .