Comparators

Lets now focus on the conditional part:

if (country === "France") {
    ...
}

The conditional part is the variable country followed by the three equal signs (===). Three equal signs tests if the variable country has both the correct value (France) and also the correct type (String). You can test conditions with double equal signs, too, however a conditional such as if (x == 5) would then return true for both var x = 5; and var x = "5";. Depending on what your program is doing, this could make quite a difference. It is highly recommended as a best practice that you always compare equality with three equal signs (=== and !==) instead of two (== and !=).

Other conditional test:

x > a: is x bigger than a?
x < a: is x less than a?
x <= a: is x less than or equal to a?
x >=a: is x greater than or equal to a?
x != a: is x not a?
x: does x exist?

Correct!

False!

Add a condition to change the value of `a` to the number 10 if `x` is bigger than 5.

var x = 6; var a = 0;

var x = 6;
var a = 0;

if (x > 5) {
    a = 10;
}

assert(a === 10);

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Logical Comparison

In order to avoid the if-else hassle, simple logical comparisons can be utilised.

var topper = (marks > 85) ? "YES" : "NO";

In the above example, ? is a logical operator. The code says that if the value of marks is greater than 85 i.e. marks > 85 , then topper = YES ; otherwise topper = NO . Basically, if the comparison condition proves true, the first argument is accessed and if the comparison condition is false , the second argument is accessed.