How do rockstar game achievements work?

The only verified information we have is about the 2005 beat 'em up video game The Warriors, which was developed by Rockstar Toronto and published by Rockstar Games. It was released for PlayStation 2, Xbox, and later re-released for PlayStation 3 and PlayStation 4. No details about achievements, trophies, or any other reward systems are mentioned in the source. Therefore, we cannot provide an explanation of how Rockstar game achievements work based on the evidence given.