What is the difference between Default and Latn?

[Dan Kreider]

I created a specialized music font, and it worked correctly in all the major music notation programs except for one, Sibelius.

What I had to do was to copy the scripts from the Latn table to the Default. Then it worked.

What is the difference between these? Where can I learn more about them? I’ve looked around online but I don’t see much. Thanks.

[Erwin Denissen]

If their shaping engine is correctly implemented, and your characters are Latin, then both should work just fine, even if your font contains both Default-Default and Latin-Default Script-Language pairs (with the exact same features).