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If you like math, this is the lesson for you as we're going to be looking at JavaScript operators and

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we have seen a little bit of these in the earlier lessons.

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So we're going to be focusing on how to use operators, what are available or what operators are available

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and the order of arithmetic operators in JavaScript.

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So if you remember from high school or public school that there is an order when you are adding, subtracting,

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multiplying or division.

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So there's a standard order of operations.

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So we do adding, subtracting, multiplication and division.

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And if we want to change around that order, then we need to wrap it with brackets.

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And there's more information available about arithmetic operators at the Modula Developer Network.

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So they've got a great example here of two plus three minus one.

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Quick, what's the answer?

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It's for this one gets a little bit more complicated.

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So we have four times three divided by two.

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So the answer here is that we're doing multiplication and then division.

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So that's the order of operation.

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So four times three is 12, divided by two is outputting six.

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This one is also a little bit more complicated.

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And we're doing a modulus and then we're also multiplying by the exponential.

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So we are not going to be exploring that in the upcoming lesson.

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But you're welcome to try that out in your console and play around with it.

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And although we are looking at Modulus and we explain that more detail as we go through the lesson,

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also there's additions.

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So of course, addition, just adding it together.

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And then there was some of the additions with strings that we saw, which is also known as concatenation,

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where we do a five plus FU ends up as a string value.

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So JavaScript again is trying to convert these as best as possible to either numbers or strings and

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adding them together.

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So if we have a boolean value plus a number, we end up with additions to booleans, we end up with

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additions and so on.

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There's also subtraction.

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So when we're subtracting a number and if we're doing a string minus three, then we're being returned

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back on a number.

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And as we saw in the last lesson, that tries to convert the string to a number.

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So that's where we get non-moving return back.

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We also have a division.

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So we've got division by all the different values and then the values that are being returned.

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Multiplication, of course.

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So we have two times.

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Two is four negative, two times two is negative four.

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And then if we multiply a value and we get not a number, but if we multiply infinity, so remember,

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anything by a zero is going to be returned back as a zero.

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But we're getting infinity.

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That's not a number.

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So this is one of the things to keep in mind.

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But very rarely are you ever going to be working with infinity so you don't have to usually worry about

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that.

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And of course, we can't multiply a string by two.

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Doesn't make sense.

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The one that we did want to look at and that might be something that might you might be not be familiar

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with is the modular operator.

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And what this is, this is the remainder essentially.

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So we get the value.

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And if we do 12 modulus five, we end up with two.

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So two is the remainder that's remaining there after we divide 12 by five.

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So we get it goes in twice, but we get a remainder of two.

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So ten divided by five is the two sets.

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We're getting the remainder.

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So that one is a little bit confusing because it is the remember remainder and then there's some other

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operators that we're not going to be exploring within the lesson.

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So there's a lot of great information on Segan module, the developer network.

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So we do need to look at order.

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And that was something that we saw that we've got multiplication, division, addition, subtraction.

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So that's the order of precedence of operator precedence and again, referring to the module of the

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developer network.

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So we get three plus four times five.

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Quick, what's the answer?

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OK, three plus four, seven times five would be 35, but we forgot the order of precedence, the operator

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precedence.

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So we're doing multiplication first.

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So four times five is 20 and then plus three.

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And that's why our answer is twenty three.

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So it does take some getting used to unless you're familiar with it from high school or public school,

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the order is still the same thing.

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And if we did want to do three plus four multiplied by five, that means that we would have to wrap

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it in brackets.

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And I'll show you quickly how that works in the console.

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So if we take a value and if we take the three rapide in brackets and then we multiply it by five,

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we're going to get 35.

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Whereas if we have three plus four times five, we're going to end up with twenty three and you get

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the picture.

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So wrapping it in brackets, just like you do with regular math outside of coding, it's going to work

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the same way.

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So keep in mind that there is an order and if you are doing some math and if you're not getting the

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value that you're expecting.

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Take a look at the order that it's being presented in there's the modulus, so we did look at this and

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I know 12 modulus five returning of two is a little bit confusing because it also means that five goes

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into 12 twice.

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So there we that number is a little bit confusing.

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But if we do 13, modulus five, you're going to see that we're returning back a value of three and

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a little bit with it.

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So we've got 13 modulus five and you see that the return is three.

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So 14 modulus five.

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What's the answer?

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Quick four and five.

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Modulus five.

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And what's the answer going to be?

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This is maybe a little bit of a trick question, but that's a zero.

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So try out some of the formulas, try some of the math operators.

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Remember the order of precedence, challenge yourself, have some fun with it.

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We're going to jump in the next lesson going into more detail about operators that are available in

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JavaScript.