Back in April of 2018 and depending upon the software you run, you may have noticed a message pop up that informs you that the application you are usingis not optimized for your Mac. This message pops up when you run a 32 bit application on macOS High Sierra. Typically, 32 bit applications tend to be older, legacy apps that may not have newer 64 bit versions. Although the application will run fine, Apple is likely gearing up to no longer support these 32 bit applications in a future version of macOS.
How to install macOS on a VM to run your 32 bit apps