One Out Example

   Pocket Cards                                                   Community Cards
Ace of Spades Ten of Spades                                         Queen of Spades Two of Clubs Jack of Spades
"Gutshot Straight Flush Draw"

Although in this example you have outs to draw to a straight or flush, we're looking at your odds to catch a (royal) straight flush, the best hand possible in texas holdem. You have only one card, the King of Spades, to make that hand. Chance of hitting your royal on the turn is 2.128%. Overall the chance of hitting on the turn or river is 4.255%. If you miss it on the turn, your chances on the river are 2.174%.

   Pocket Cards                                                   Community Cards
Four of Spades Four of Diamonds                                         Two of Diamonds Nine of Hearts Four of Clubs
"Improving Three-of-a-Kind to Four-of-a-Kind"

We are still talking about hitting one particular out. This example would be your chance of turning a set into a four-of-a-kind. Your one out is the only remaining Four in the deck, the Four of Hearts. The chances are the same as the first example.