The Cheetahs have the trademark Beretta open top slide and a lightweight aluminum frame. They are double action/single action with a frame-mounted safety. You can find them in .380 ACP, .32 ACP, and .22 LR.
Beretta started using the name Cheetah sometime in the 90s, but they were first released back in 1975 as simply the Model 81 and 84. The 81 was a .32 ACP with a double column 12-round magazine. The 84 was basically identical but it was chambered for .380 ACP with a 13-round mag.
The 80-series was designed for the law enforcement market, primarily in Europe and other countries outside of the US where small calibers were considered acceptable for duty use. It’s had a fair amount of success in that role and I believe they are still in use in some of those places.
In the early 80s, Beretta debuted single stack versions of the Cheetahs: the Model 82 with 9+1 rounds of .32 ACP and the 85 with 8+1 rounds of .380.
These four models were and still are the most popular and well known variants of the Beretta Cheetah. They all have the same exterior dimensions. They all have 3.8-inch barrels. But they’re not the only Cheetahs.