JS Operators

Operators are for Mathematical and Logical Computations

The Assignment Operator = assigns values

The Addition Operator + adds values

The Multiplication Operator * multiplies values

The Comparison Operator > compares values

JavaScript Assignment

The Assignment Operator (=) assigns a value to a variable:

Assignment Examples

let x = 10;

JavaScript Addition

The Addition Operator (+) adds numbers:

Adding

let x = 5;

let y = 2;

let z = x + y;

JavaScript Multiplication

The Multiplication Operator (*) multiplies numbers:

Multiplying

let x = 5;

let y = 2;

let z = x * y;

Types of JavaScript Operators

There are different types of JavaScript operators:

• Arithmetic Operators
• Assignment Operators
• Comparison Operators
• Logical Operators
• And more ...

JavaScript Arithmetic Operators

Arithmetic Operators are used to perform arithmetic on numbers:

Arithmetic Operators Example

let a = 3;

let x = (100 + 50) * a;

Note: Arithmetic operators are fully described in the JS Arithmetic chapter.

JavaScript String Addition

The + can also be used to add (concatenate) strings:

Example

let text1 = "John";

let text2 = "Doe";

let text3 = text1 + " " + text2;

The += assignment operator can also be used to add (concatenate) strings:

Example

let text1 = "What a very ";

text1 += "nice day";

Note: When used on strings, the + operator is called the concatenation operator.

Adding Strings and Numbers

Adding two numbers, will return the sum as a number like 5 + 5 = 10.

Adding a number and a string, will return the sum as a concatenated string like 5 + "5" = "55".

Example

let x = 5 + 5;

let y = "5" + 5;

let z = "Hello" + 5;

Note: If you add a number and a string, the result will be a string!

JavaScript Assignment Operators

Assignment operators assign values to JavaScript variables.

The Addition Assignment Operator (+=) adds a value to a variable.

Assignment

let x = 10;
x += 5;

Note: Assignment operators are fully described in the JS Assignment chapter.

JavaScript Comparison Operators

Comparison operators are used to compare two values.

Comparison operators always return true or false.

Example

let x = 5;

let result = x > 8;

All the comparison operators above can also be used on strings:

Example

let text1 = "A";

let text2 = "B";

let result = text1 < text2;

Note that strings are compared alphabetically.

Note: Comparison operators are fully described in the JS Comparisons chapter.

JavaScript Logical Operators

Note: Logical operators are fully described in the JS Logical chapter.