WEBVTT

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Now these symbols, such as the greater or the lesser than or the three equals signs, are known in programming

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as comparatives because they allow us to compare two different values.

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So we've seen and used the three equals signs.

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And this is checking whether if the left hand side is equal to the right hand side.

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Now you can also use a exclamation mark and two equal signs to check whether if the left hand side is

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not equal to the right hand side, as well as whether if something is greater then something else or something

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is lesser than something else or greater than equal or lesser than equal.

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And these comparatives give our conditionals, like if and else statements, a lot more flexibility.

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Now some of you might have seen another type of equality comparative.

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So instead of using a three equal sign sometimes you see people using two equal signs.

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Now there's a big difference however between the two of these.

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So let's say we have a variable a and it's equal to 1 and then we have a variable b that's equal to

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the string 1.

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So this is 1 as a piece of text essentially, and they have different data types,

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because if we say type of a we get number and type of b we get string.

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So at this point if we check to see if a triple equals b, then if it's true we will get console.log

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“yes”

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and if it's false then we will get console.log “no”.

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So if I go ahead and hit enter right now then you can see that we get no, a does not triple equal b.

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But, however, if I was to modify this and change it to if a is a double equal to b and I hit run, then

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you can see we get

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yes

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in this case.

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So the important difference between three equal signs and two equal signs is that, even though they both

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check for equality, with three equal signs

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it’s also checking to see that the data types are matching, whereas with two equal signs it doesn't care

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about the data types.

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So let's head back to our love calculator and maybe one more thing that we could ask of it.

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What if we could separate our love score ranges a little bit more finely?

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So, for example, if we could have a different message for people who got between 1 and 30, then people

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who got between 30 and 70, and those who were ultra lucky and got between 70 and 100.

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How would we be able to do that?

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Well, we would have to learn how to combine different comparatives, and we'll tackle that in the next

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lesson.

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So that's all for me for today.

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And I will see you on the next lesson.