Age spots, sometimes called "liver spots," are brown, flat spots that appear on the skin.
The Cleveland Clinic explains more about age spots and what you can do about them:
Age spots typically occur as a result of exposure to the sun.Age spots most commonly occur on the face, arms, hands, feet and back.Age spots normally do not cause harm, but a dermatologist may be able to remove them if they bother you.Wearing sunscreen can help prevent age spots from worsening.
Source:
http://www.medicinenet.com/script/main/art.asp?articlekey=176042