Norn was an offshoot of Old Norse. It was spoken in the Shetland Islands and Orkney Islands of the United Kingdom. After the islands were ceded to Scotland in the 15th century, Norn slowly gave way to Scots. It is not known exactly when Norn became extinct; it may have been spoken in some parts of these islands until the 18th century. Isolated snippets of the language and loan-words adopted into English or Scots survived the death of the language.
Relatively little written Norn has survived. What we do have includes a version of the Lord's Prayer.
Dialects of Norse were also formerly spoken on mainland Scotland - for example, in Caithness - but here they became extinct many centuries before Norn died on Orkney and Shetland. Hence, some scholars speak about "Caithness Norn" also, but others avoid this. Even less is known about "Caithness Norn" than about Orkney and Shetland Norn.