Single Barrel Whiskey,
This is basically a whiskey that for what ever reason the distiller believes is above and beyond delicious. Every single bottle comes from a single aging barrel, each bottle is bottled separately with each bottle having the barrel number and bottle number, and usually the beginning and end date for that barrel of liquor.
Single Malt Whiskey, mash is made of mostly malted barley. If this whiskey is made at one distillery it will probably be called a single malt whiskey. You can use other grain to make malt whiskey but it must be designated what it is, like Rye Malt whiskey or Wheat Malt Whiskey. There are a few rules for malt whiskey.
ABV level not exceeding 80%, Mash must be at least 51% malted barley, must be stored in new oak barrels, it must be aged at least 2 years, can’t have any coloring or additives, has not been blended with any other type of whiskey.