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Welcome back.

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Let's talk about a important term when it comes to programming, and that is operator precedence.

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Now, what does that mean?

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Again, we're using our knowledge from math class.

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It's the idea that if I do 20 plus three times four, it means that different operators have precedence

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over different ones.

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That is, we multiply this first equals to 12 and then 20 gets added to 12.

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Because the Python interpreter is going to follow a basic set of rules.

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For example, if I do 20 minus three here.

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And let's print this out.

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Click Run.

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I get eight because three times four gets evaluated first, which equals to 12, and then subtract it

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from 20.

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It's not that this goes first and then we multiply 17 by four.

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And this operator precedence shouldn't be new, right?

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If you've taken any sort of math class.

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You understand that this is how well math works.

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And this works the same in all programming languages.

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So the order is this.

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First we follow the brackets.

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So whatever is wrapped in a bracket, we do first.

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The second is we do the power of.

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So whatever is done in the power of will be after parentheses.

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For example, if I do parentheses here.

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And then to the power of, let's say two or let's do plus two to the power of two.

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Well, the first operation that will happen is 20 minus three, because that's the first precedence.

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And then we do two to the power of two, because that's the next precedence.

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And then only after we do that, we add these two together.

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If I click Run.

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I get 21, which again makes sense.

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17 plus four.

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After the power of we have the multiplication and division.

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And then finally, the last precedence is addition and subtraction.

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Now, this isn't going to be a math class.

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Some people really love math.

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Some people really don't.

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But I want to just give you this basic understanding of operator precedence when you see it.

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We'll do some exercises here to get accustomed to it.

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But trust me, this is as mathy as we're going to get in this course.

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The math part of the course is, well, just here.

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It's going to get a lot more interesting as we learn about different data types.

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I'll see you in the next one.

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Bye bye.