With the August 2009 release of Mac OS X 10.6 Snow Leopard, Menlo was introduced as the default monospaced font instead of Monaco in Terminal and Xcode, However, Monaco remains a part of macOS.
In the August 2009 update to Mac OS X 10.6 Snow Leopard, Menlo replaced Monaco as the default monospaced font for Terminal and Xcode applications, yet Monaco continues to be included in macOS.