Two Pair - This contains two distinct pairs of cards and a 5th card. The highest pair wins ties. If both hands have the same high pair, the second pair wins. If both hands have the same pairs, the high card wins. Pair - One pair with three distinct cards.
High card breaks ties.
High Card - Any hand which does not qualify as any one of the above hands. If no player has a pair or better, then the highest card wins. If multiple players tie for the highest card, they look at the second highest, then the third highest etc. Poker is, after all, a gambling game. After that the players will begin to bet into the pot in the middle.