45s
First came the 45 Colt.
Second came the 45 S&W or 45 Scofield. The 45 Colt was too long for the S&W frame of the time.
Third came the 45 Government. The 45 Schofield would allow only every other chamber to be loaded in the SAA due to the wide rim. The 45 Government worked in both at a slightly increased risk of getting the rim under the extractor in the S&W. This cartridge reached the civilian market where it was known as the 45 Short Colt. Old civilian cartridge boxes may be found bearing the designation of either 45 Government or 45 Short Colt.
Fourth came the 45 Revolver, also known as the 1909 Colt 45. It was intended for the New Service Model 1909 and had a wide rim like the Schofield while the case was just a tad longer than the 45 Colt.
Fifth came the 45 ACP for the Colt 1911.
Sixth came the 45 AR, a rimmed version of the 45 ACP for revolvers.
Seventh came the 454 Casull, today a slightly stretched version of the 45 Colt loaded to much higher pressures..
Eigth came the Winchester 45 Magnum, a streched version of the 45 ACP.
Ninth came the 45 GAP, a shortened version of the 45 ACP loaded to higher pressure..
Tenth came the 460 S&W, a still longer version of the 45 Colt loaded to very high pressures.
I leave out any proprietary 45s from small operations such as the 460 Rowland.
BTW: Within the last month or so I saw a box of 45 Short Colt by Fiocchi at a gun show. They may be still loading it.