Tennessee is a style of whiskey that differs from Bourbon whiskey very slightly in production. Every other process is the same, though the mash bill need not contain the same quantity of corn.
The additional process is known as the Lincoln County Process. It was named for Lincoln County, in which Jack Daniel first distilled. This process involves filtering the spirit through sugar maple charcoal. This process removes some of the congeners and esters in the spirit and proffers a slightly smoky character. There are two distillers who produce Tennessee whisk(e)y; George Dickel and the famed Jack Daniel.