Comparison and Logical operators are used to test for true or false.
Comparison Operators
Comparison operators are used in logical statements to determine equality or difference between variables or values.
Given that x=5, the table below explains the comparison operators:
Operator | Description | Comparing | Returns | Try it |
---|---|---|---|---|
== | is equal to | x==8 | false | Try it » |
x==5 | true | Try it » | ||
=== | is exactly equal to (value and type) | x==="5" | false | Try it » |
x===5 | true | Try it » | ||
!= | is not equal | x!=8 | true | Try it » |
!== | is not equal (neither value or type) | x!=="5" | true | Try it » |
x!==5 | false | Try it » | ||
> | is greater than | x>8 | false | Try it » |
< | is less than | x<8 | true | Try it » |
>= | is greater than or equal to | x>=8 | false | Try it » |
<= | is less than or equal to | x<=8 | true | Try it » |
How Can it be Used
Comparison operators can be used in conditional statements to compare values and take action depending on the result:
if (age<18) x="Too young";
You will learn more about the use of conditional statements in the next chapter of this tutorial.
Logical Operators
Logical operators are used to determine the logic between variables or values.
Given that x=6 and y=3, the table below explains the logical operators:
Operator | Description | Example |
---|---|---|
&& | and | (x < 10 && y > 1) is true |
|| | or | (x==5 || y==5) is false |
! | not | !(x==y) is true |
Conditional Operator
JavaScript also contains a conditional operator that assigns a value to a variable based on some condition.
Syntax
variablename=(condition)?value1:value2
Example
Example
If the variable age is a value below 18, the value of the variable voteable will be "Too young, otherwise the value of voteable will be "Old enough":
voteable=(age<18)?"Too young":"Old enough";
Try it yourself »
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