~/Library/Fonts — will be accessible only that user
Alternatively, to make fonts accessible to all users, you can install them into either of:
if Classic is installed, Classic fonts will be installed with your system folder.
The classic fonts are available to Mac OS X applications and are used when booting into Mac OS 9.
Only admin users can install into /Library/Fonts or /Network/Fonts
Mac OS uses fonts inside of /System/Library/Fonts and they should not be removed. Adding to this folder will cause them to be available to all users.