Poker is a card game played with a standard deck of 52 cards (although some variant games have more or less than that). The cards are ranked from high to low: Ace, King, Queen, Jack, 10, 9, 7, 6, 4 and 3. In most cases the highest poker hand wins. Sometimes there are wild cards (like jokers) that can take the place of any other card and help make a higher hand.
When playing poker players put bets into the middle of the table called the pot, to win the hand. Each player must place an ante, which is a forced bet before they can see their cards. They then have the option to raise, call or fold their hand.
Players can only raise on the next betting round after they have seen their cards. If they are unsure of their hand, they may raise a bit lower than the previous player to give them an advantage. They can also use signals to let other players know whether they are bluffing or have a strong hand.
The aim of the game is to extract maximum value from your winning hands and minimise losses from losing ones. To do this you need to develop quick instincts by practicing and watching other players. The more you play and observe, the better you will become. Ideally, you should focus on developing your instincts rather than trying to learn and apply complex systems.