< p > The game is played with a standard deck of cards consisting of 25 different types of cards, each with a unique color or symbol. Players take turns drawing one card at a time from the deck and play it matching the color or symbol from one of their existing cards on the table. p >
< p > If a player has only one card left in their hand, they must say "uno" to alert the other players. However, if they fail to do so and another player notices that they only have one card remaining, they can call "uno" and the original player must draw two cards as a penalty. The game continues until one player has played all their cards, in which case that player wins. p >
< p > Players can form only one vertical or horizontal line of connected cards, with two cards forming a line being a basic match. Restrictions are in place to prevent extended lines from forming, maintaining a dynamic and competitive environment. The browser-based game does not require download or registration and is accessible immediately across various devices.