Electrolytic cells are composed of an electrolyte (usually water or another solvent capable of dissolving various ions of interest), a cathode and an anode.
An Electrolytic cell is powered by electricity to produce a change in the chemicals in the cell, providing the energy to convert the chemicals into ones with higher energy storage.
In contrast, a Galvanic Cell uses the chemical energy of the high-energy chemicals reacting to generate electricity - the opposite of the electrolytic cell.
To reflect this difference, the Anode and Cathode in the two types of cell have different polarities assigned to them - which can be very confusing!
See also: Electrolysis, Galvanic Cell