I believe the Irish taught the Scots to make usequebagh or whisky. Scots renamed it scotch. Other varieties of scotch are Islay named because it comes from the small islands off the north of Scotland. There is also a difference in lowland and highland scotch usually varying by the amount of peat in the water used for distilling, Laphroig having a high peat content, and Oban a lower peat content. Aging in sherry casks also. see also scotches

contrary to what Webster 1913 says, the Scots (being the people of Scotland), do not like being referred to as scotch. They prefer the appellation Scots.