Norn was a North Germanic language spoken in the Orkney and Shetland Islands until 19th century. Like the Scandanavian languages, it is a descendant of Old Norse, and was a product of dark age Viking settlements on the islands. Comparisons with other Nordic tongues reveals its unique internal innovations and developments. Try the "Our Father" (from Low's "A Tour through the Islands of Orkney and Shetland" 1879)
Fy vor or er i Chimeri. Halaght vara nam dit. La Konungdum din cumma. La vill din vera guerde i vrildin sindaeri chimeri. Gav vus dagh u dagloght brau. Forgive sindorwara sin vi forgiva gem ao sinda gainst wus. Lia wus ik o vera tempa, but delivra wus fro adlu idlu. For do i ir Kongungdum, u puri, u glori, Amen.
You can see the tremendous sound changes in particular words. Norn fy "father" has come a long way from faðer. Other words are preserved quite well, like konungdum "kingdom" (compare Old Icelandic konungdomr). Let's take a look at the prayer in Old Norse (as printed in Rost's "Lords Prayer in 500 Languages" 1905).
Faðer vor som ast i himlün, halgað warðe þit nama. Tilkomme þit rikie. Skie þin vilie so som i himmalan so oh bo iordanne. Wort dahliha broð gif os i dah. Oh forlat os vora skuldar so som oh vi forlate þem os sküldihi are. Oh inleð os ikkie i frestalsan utan frels os ifra ondo. Tü rikiað ar þit oh mahtan oh harlihheten i ewihhet. Aman.
So now with the ancestral form at our fingertips, we can notice many other interesting changes. Vowels changed in the unstressed position, perhaps to a schwa (e.g., amen > aman). Norn halaght "holy" shows a normal development from a later East Norse metathesis (Old Icelandic heilagr). Stylistically, the author captured the Nornish sandhi (gav vus as pronounced, instead of careful speech gav us).