<P> Coin flipping was known to the Romans as navia aut caput ("ship or head"), as some coins had a ship on one side and the head of the emperor on the other . In England, this was referred to as cross and pile . The expression Heads or Tails results from heads and tails being considered complementary body parts . </P> <P> During a coin toss, the coin is thrown into the air such that it rotates edge - over-edge several times . Either beforehand or when the coin is in the air, an interested party calls "heads" or "tails", indicating which side of the coin that party is choosing . The other party is assigned the opposite side . Depending on custom, the coin may be caught; caught and inverted; or allowed to land on the ground . When the coin comes to rest, the toss is complete and the party who called correctly or was assigned the upper side is declared the winner . </P> <P> It is possible for a coin to land on its edge, usually by landing up against an object (such as a shoe) or by getting stuck in the ground . However, even on a flat surface it is possible for a coin to land on its edge, with a chance of about 1 in 6000 for an American nickel . Angular momentum typically prevents most coins from landing on their edges unsupported if flipped . Such cases in which a coin does land on its edge are exceptionally rare and in most cases the coin is simply re-flipped . </P> <P> The coin may be any type as long as it has two distinct sides; it need not be a circulating coin as such . Larger coins tend to be more popular than smaller ones . Some high - profile coin tosses, such as the Cricket World Cup and the Super Bowl, use custom - made ceremonial medallions . </P>

Can you flip a coin on its side