Spit in the Ocean / Cincinnati
This page describes several shared (community) card poker games, featuring a card or cards on the table which can be used by all players as part of their hand. The reader is assumed to be familiar with the general rules of poker.
This was probably the first shared card game, with just a single communal card dealt to the table. It is described in the 1926 edition of the US Playing-Card Company's Official Rules of Card Games as a variant of Wild Widow, which is a five-card draw game with a card dealt face up to indicate what is wild. The innovation was to players to use this indicator card as though it was part of their hands.
Four cards are dealt to each player and a card is dealt face up to the table. This table card and all cards of the same rank are wild. There is a betting round.
Now each player in turn can discard any number of cards and receive replacements from the dealer. (Some rules say that one cannot discard more than two cards, but this makes little difference since it is generally foolish to discard three or all four cards.) There is a second betting round followed by a showdown in which the hands consist of a player's four private cards plus the communal wild card. The highest hand wins the pot.
Five cards are dealt face down to each player and five cards face down to the table. The players look at their hands.
The dealer turns the table cards face up one at a time. After each card is turned up, there is a round of betting.
After the fifth and final betting round there is a showdown, won by the highest hand. A player's five-card hand may be made from any combination of hole cards and table cards.
A popular variation is to specify that the holder of the highest card of the suit of a particular table card - often the last card turned over, or sometimes the third card turned over - splits the pot with the highest hand. Or the high hand may split the pot with the holder of the highest card of that suit if the table card is 8 or higher but with the lowest card of the suit if the table card is 7 or lower.
Alternatively, it may be specified that the last table card turned over and all the cards of the same rank are wild.
Sometimes Low Hole Cincinnati is played, in which each player's lowest hole card is wild for that player, along with any others of the same rank.
This is similar to Cincinnati, but only four cards are dealt to each player and four cards to the table. The table cards are turned up one at a time with a betting round after each. After the fourth betting round there is a showdown for the highest hand, in which players can use any combination of table cards with their hole cards to make a five-card hand.
Three hole cards are dealt to each player and there is a betting round. Then four cards are dealt face down to the table and turned over one at a time, with a betting round after each card is turned.
In this game the lowest of the four table cards is wild, along with any other cards of the same rank. In the showdown players can use any combination of hole cards and table cards to make a five-card hand, and the highest hand wins the pot.