D'ni (pronounced duh-nee) is the
mythical civilization/
place/
language which serves as the major backstory device for the
video games
Myst and
Riven. The D'ni had discovered how to write books which
linked to other ages.
Misspelled as "dunny" in Myst.
Myst and Riven take place two generations after the destruction of D'ni.
For More info read the trilogy: Myst: The book of Atrus, Myst: The book of Ti'ana, Myst: The book of D'ni