The first step to mastering poker is to learn the hand rankings. These rankings remain the same for all forms of poker.
We'll start with the worst hand:
Here you have nothing. In the event of two people both having nothing, the hand with the highest card will win.
Therefore hand A (Ace high) beats hand B (King high).
If two hands have the same high card, the next highest card is the deciding factor.
Continuing with the next best hand:
Here you have a pair. In the event of two people both having a pair, the hand with the highest pair will win.
Therefore hand B (pair of kings) beats hand A (pair of Queens).
If two hands have the same pair then it is the next highest card which is the deciding factor. This deciding card is called a kicker.