Ill take a stab at that 1.
By definition wine is an alcholic beverage fermented form grapes. Although other fruits and plants are fermented into wine it is normally called fruit wine or country wine or just using the actual product that was fermented such as Apple wine or Barley wine.
Cider, Im guessing you mean hard cider as cider is just the juice of fresh presed apples and Hard Cider is the result of fermenting cider and the abc usually varies from 3%-8 1/2%.
Sherry is a fortified wine made in a small region in Spain. It is fortified with Brandy. It gets its taste from using nly a few ceratin varietals and then by actually leaving it in barrels with more space in there then typical to allow for a certain yeast called Flor to flourish.