The terms are quite technical, but improvements for the first resulted in benchmarks where Chrome 55 used 50 percent less memory than Chrome 53.
Numbers for the second set of improvements, zone memory, resulted in Chrome 55 using 35 percent less memory than Chrome 53.
The benchmark tests only included loading a limited set of websites, such as Facebook, The New York Times, Hacker News, CNN, Reddit, Twitter, Imgur, and YouTube, but Google expects these results to be universal.
Quietly, the Chrome browser has become a memory hog in recent years. No matter the brand behind a browser maker, users will change ship to other more speedy and responsive browsers if Chrome becomes too laggy.
Increased memory usage and constant crashes are the most cited reasons why most users have abandoned Firefox, which now has a smaller market share than Safari.
Google launched Chrome 54 earlier this week. The search giant is scheduled to release Chrome 55 in mid-November.