What this coin looks like (obverse, reverse, mint mark location, special features, etc.):
One major variety is the 1836/1336 Capped Bust Half Dollar overdate error. This resulted in an 1836 date struck over an 1336 date. The easiest way to identify this coin is to note that parts of the first "3" in "1336" is seen within the "8" in the 1836 date - particularly towards the bottom half of the "8". A very subtle part of the "1" is seen doubled at the bottom and parts of the "6" are subtly doubled as well - though extremely hard to detect. The 1836/1336 overdate was the result of the engraver recutting the "8" over the "3" punch on the coin die.
Coin valuation chart: Typical coin prices, values and worth per grade or condition - in USD