P- Put money in the pot
R- Draw card
In blackjack, the player is typically dealt two cards; one face down and one face up. The goal of the game is to make as many total points as possible by playing cards that total more than the number shown on your hand, while avoiding having any cards total less than that number.
For example, if you are playing with a hand of 4-card draw and are faced with a 7 on the table, you would want to play an Ace (high card), two 2s, or a 3 because those combinations would total more than 7. .
If you are dealt a low card (1, 2, 3, or 4), then it is advantageous to either hit or stand (because those combinations will not total more than the number shown on your hand). However, if you are dealt a high card (5 or 6), then it is advantageous to hit (because those combinations will total more than the number shown on your hand).
When deciding whether or not to hit or stand, there is another factor to consider: whether or not your dealer has any blackjacks. If your dealer has a blackjack (a hand of 21), then you should definitely hit because that combination totals 21.
However, if your dealer does not have a blackjack (a hand of 18), then you should probably stand because that combination totals 18.
The final decision depends on what else is going on in the game and whether or not you believe that you can make more points by hitting or standing.