Comparison

One of the most useful functions of any coding language is the ability to compare two or more values and return whether or not they are equal. Almost every conditional statement you write will make use of these comparison operators.

Comparison Operators

In JavaScript, data-type does not usually matter when comparing two values. Unless specifically stated otherwise, the values are converted to the same type at the time of comparison.

Name	Operator	Description	Example
Equal	==	returns true if the values are equal, regardless of data-type	3 == 3 //true; '3' == 3 //true
Not Equal	!=	returns true if the values are not equal, regardless of data-type	3 != 4 //true; '3' != 3 //false
Strict Equal	===	returns true ONLY if the values are equal AND the same data-type	3 === 3 //true; '3' === 3 //false
Strict Not Equal	!==	returns true if the values are not equal OR not the same data-type	3 !== 4 //true; '3' !== 3 //true
Greater than	>	returns true if value A is larger than value B	4 > 3 //true; 3 > 4 //false
Greater than or equal	>=	returns true if value A is larger or the same as value B	4 >= 3 //true; 4 >= 4 //true; 3 >= 4 //false
Less than	<	returns true if value A is smaller than value B	3 < 4 //true; 4 < 3 //false
Less than or equal	<=	returns true if value A is smaller or the same as value B	3 <= 4 //true; 3 <= 3 //true; 4 <= 3 //false
AND	&&	returns true ONLY if value/condition A AND value/condition B are true	true && true //true; true && false //false
OR	||	returns true if EITHER value/condition A OR value/condition B are true	true|| false //true; false|| false //false

File Location

We will be working in the following file:

    javascript-library
        └── 0-PreWork
        └── 1-Fundamentals
            └── 1-Grammar-and-Types
            └── 2-ControlFlow-and-ErrorHandling
            └── 3-Loops
            └── 4-Functions
            └── 5-Expressions-and-Operators
                01-assignment.js 
                02-comparison.js <----You will be working in this file.

Practice

1. In comparison.js, create a variable and assign it a value.

2. Use the comparison operators to compare the variable to other values and print the results.

3. Use conditional statements and comparison operators to create a program with the following results:

If a person's age is over 25, they can rent a car. If a person's age is over 21, but less than 25, they can have a beer. If a person's age is over 18, but less than 21, they can vote. If a person's age is less than 18, make fun of them for being a child.