Help please! ...Describe the difference between galvanic cell and an electrochemical cell. Give examples.?

a galvanic cell undergoes the oxidation/reduction reaction upon closing the circuit
it is a spontaneous reaction in which electrons are transfered,
producing a positive voltage,
like discharging a battery
http://en.wikipedia.org/wiki/Galvanic_cell

http://bilbo.chm.uri.edu/CHM112/tables/redpottable.htm
provides the following reduction voltages
reduction: Pb2+(aq) + 2 e-    Pb(s)    Eo = -  0.125  volts
reduction: Sn2+(aq) + 2 e? --->  Sn(s)    Eo = -  0.137  volts


to get an oxidation/reduction reaction, we reverse one of them
reduction: Pb2+(aq) + 2 e-    Pb(s)    Eo = -  0.125  volts
oxidation: Sn(s) --->:  Sn2+(aq) + 2 e?   Eo = +  0.137  volts
this would be a galvanic cell, that redoxs spontaneously, because the net voltage is "+"


had we reversed the other one:
oxidation: Pb(s)  ---> Pb2+(aq) + 2 e-     Eo = + 0.125  volts
reduction: Sn2+(aq) + 2 e? --->  Sn(s)    Eo = -  0.137  volts
this would be an electrochemical cell, that will redox spontaneously, because the net voltage is "-"


an electrolytic cell is one that must be forced, by subjecting it to a supply of DC voltage..
like recharging a battery
http://en.wikipedia.org/wiki/Electrolytic_cell