In one of the takeaways from the latest WWDC conference it was announced that "...macOS High Sierra will be the last macOS release to support 32-bit apps without compromises." It's a 64-bit world out there, so if you have software titles that are still 32-bit*, you might want to send queries to their author(s) about future compliance to Apple's 64-bit OS--if you were to upgrade to the next Apple OS you may lose that software's functionality or use, altogether. "If you were to upgrade to the next Apple OS you may lose that software's functionality or use." (all together) I knew you'd think that! *OS High Sierra pops up a warning window if the app you just launched is 32-bit.