Other useful directories that aren't specified by XDG.

Home Directory

The current user's home directory. Windows %USERPROFILE% Unix (macOS/Linux/FreeBSD) $HOME

Application directories

Common application directories. Windows The Programs Special Folder, the Common Programs Special Folder macOS /Applications Linux/FreeBSD $XDG_DATA_HOME/applications, $HOME/.local/share/applications, /usr/local/share/applications, /usr/share/applications

Font directories

Common font directories. Windows %SYSTEMROOT%\Fonts, %LOCALAPPDATA%\Microsoft\Windows\Fonts macOS $HOME/Library/Fonts, /Library/Fonts, /System/Library/Fonts, /Network/Library/Fonts Linux/FreeBSD $XDG_DATA_HOME/fonts, $HOME/.fonts, $HOME/.local/share/fonts, /usr/local/share/fonts /usr/share/fonts