While several brands of fruit snack are called "licorice," most of them technically aren't. Licorice is actually the root of a plant called Glycyrrhiza glabra which has a somewhat sweet flavor and is used for a variety of things, including as a flavoring for candy. Only what is commonly referred to in the United States as "black licorice" actually contains true licorice flavor.
Licorice root is known for a variety of medicinal uses including as an expectorant (it's often used in cough syrups), as a treatment for ulcers and an antiviral agent for things like shingles, as a bowel antispasmodic agent for things like irritable bowel syndrome, and as a remedy for some allergies (such as pet allergies).
Licorice candy is flavored with licorice root and usually anise oil (which has a similar flavor) as well. The essential ingredients are binder (starch, flour or gum arabic), licorice extract, and sweetener (sugar). In the U.K., licorice allsorts (variety licorice candy) are popular, and in other parts of Europe, salty licorice (which is flavored with Ammonium Chloride) is common. In the U.S., true licorice is known as "black licorice", which is redundant. "Red licorice" is technically not licorice.