Horns are:

• Made of bony core covered by a thin layer of keratin, the same material as your fingernails;
• Slow growing and permanent; they are not shed each year;
• More like daggers than branches;
• Usually grown by both sexes; and
• Usually grow in yearly "rings" that mark the animal's age.

Antlers are:

• Fast-growing bone that is shed each year
• Usually grown only by males (both sexes of caribou grow antlers); and
• Often branched (but the number of points does not signify age).