Ok, have a little time before work.
Basically, card counting in blackjack works like this.
Sets of cards are assigned -1, 0 and +1.
The table below shows these for each face value.
|-1||5||10 J Q K A|
|0||3||7 8 9|
|+1||5||2 3 4 5 6|
As cards are dealt, a running total is made for each of the cards.
If everything is randomized, the total tends to be 0 or near 0 due to cards having an equal chance of being drawn on both the +side and -side.
However, there are times when this balance dose not stay near 0.
This is what gives card counting an advantage.
An example of a running total:
We can see the balance of the deck has shifted to the +side.
In blackjack you'd want to bet more because the deck is favoring the player and the dealer has a higher chance of a bust (going over 21).
This kind of counting technique can be used in Pick 3 and Pick 4; other lotteries as well, but we'll stick to this for now.