Two Outs Example

   Pocket Cards                                                   Community Cards
Two of Spades                                         Seven of Diamonds Ace of Hearts Eight of Clubs
"Improving a Pocket Pair to a Set"

This looks like a bad flop for you. Probably shouldn't have been playing pocket twos anyways! You have two outs to improve that hand to a set of Twos. The Two of Clubs and the Two of Diamonds. Chance of hitting a Two on the turn is 4.255%. Chance of hitting a Two by the end of the hand is 8.418%. If you don't get a Two on the turn, your chance of hitting it on just the river is 4.348%.

   Pocket Cards                                                   Community Cards
Jack of Diamonds Ten of Diamonds                                         Eight of Diamonds Nine of Diamonds Nine of Clubs
"Outside Straight Flush Draw"

Another example with two outs. You have an outside straight flush draw. Your two outs would be the Queen of Diamonds or the Seven of Diamonds. Same chances as above to hit one of those two cards.