Most poker games do not rank suits; the ace of clubs is just as good as the ace of spades. However, small issues (such as deciding who deals first) are sometimes resolved by dealing one card to each player. If two players draw cards of the same rank, one way to break the tie is to use an arbitrary hierarchy of suits. The order of suit rank differs by location; for example, the ranking most commonly used in the United States is not the one typically used in Italy.
Cards are always compared by rank first, and only then by suit. For example, using the "reverse alphabetical order" ranking, the ace of clubs ranks higher than any king, but lower than the ace of diamonds. High card by suit is used to break ties between poker hands as a regional variance, but more commonly is used in the following situations, as well as various others, based upon the circumstances of the particular game.