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People make decisions every day.

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For example before you go outside

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you kind of have an IF statement that says,

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IF it's raining,
THEN I need to get my jacket.

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And, computers are amazing once you decide those kinds of statements,

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that they can reliably execute those things at unbelievable speed.

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And so, a computer program really

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is a little bit of math and some

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IF statements, where the decision gets made.

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So, in this puzzle the

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IF block helps the zombie make a decision,

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it checks something.

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For example let's use the block that says, "if there's a path to the left,"

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and put a "turn left" command inside it.

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So, we're telling the zombie to check its surroundings,

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see if there's that path on the left,

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and if so, make that turn.

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And then we use the "move forward" block inside this "repeat"

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to get it to keep moving forward as long as

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it just wants to go straight.

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Then when there's the turn, the IF block
will tell it to make this turn to the left.

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And you can see, if we do that

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if we're taking the turn to the left and otherwise moving forward, 
we'll achieve our goal.

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So it's an example of using an IF statement,

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which is really a fundamental concept in computer programming.

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One of the first things I learned was how to write a program to play tic-tac-toe.

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So I had IF statements to say okay,

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IF the other person is about to win go ahead and block that spot.

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So have fun learning how to use IF statements. It's a key concept.