**What is an operator?**

Consider a simple expression 2 + 5 equals to 7. Here, 2 and 5 are called operands and the ‘+’ is called operator. JavaScript supports the following 5 types of operators:

- Arithmetic Operators
- Comparison Operators
- Logical (or Relational) Operators
- Assignment Operators
- Conditional (or ternary) Operators

** Arithmetic Operators**

JavaScript supports the following arithmetic operators −

Lets take tow variable A= 10 B = 20, then −

Sr.No | Operator
and Description |
---|---|

1 | + (Addition) Adds two operands
Ex: A + B will give 30 |

2 | – (Subtraction) Subtracts the second operand from the first
Ex: A – B will give -10 |

3 | * (Multiplication) Multiply both operands
Ex: A * B will give 200 |

4 | / (Division) Divide the numerator by the denominator
Ex: B / A will give 2 |

5 | % (Modulus) Outputs the remainder of an integer division
Ex: B % A will give 0 |

6 | ++ (Increment) Increases an integer value by one
Ex: A++ will give 11 |

7 | — (Decrement) Decreases an integer value by one
Ex: A– will give 9 |

Note − Addition operator (+) can you to add two numbers and also to concat strings . e.g. “a” + 10 will give “a10”.

**Comparison Operators**

Here is the complete set of JavaScript comparison operators:

(Let’s assume variable a=100 and variable b=200)

Sr No | Operators
and Description |
---|---|

1 | `= = (Equals) Checks whether the values of two operands are equal or
not, when yes, then the condition becomes true.
Ex: (a==b) is not true. |

2 | != (Not Equal) Checks whether the values of two operands are equal or
not, if the values are equal, then the condition becomes false.
Ex: (a!=b) is true. |

3 | > (Greater than) Compare two numbers if first is greater than second then
return true.
Ex: (a > b) is not true. |

4 | < (Less than) Compare two numbers if first is less than second then
return true.
Ex: (a < b) is true. |

5 | >= (Greater than or Equal to) Checks if the value of the left operand/expression is
greater than or equal to the value of the right operand, when yes, the
condition becomes true.
Ex: (a >= b) is not true here. |

6 | <= (Less than or Equal to) It Checks whether the value of the left
operand/expression is less than or equal to the value of the right operand,
when yes, the condition becomes true.
Ex: (a <= b) is true here. |

**Logical Operators**

Here is the complete set of JavaScript logical operators:

(Let’s assume variable A=100 and variable B=200)

Sr No | Operators and
Description |
---|---|

1 | &&(Logical AND) When both the operands are non-zero, the condition is true.
Ex: (a&&b) is true. |

2 | || (Logical OR) When any of the two operands are non-zero, the condition becomes
true.
Ex: (a||b) is true. |

3 | !(Logical NOT) Reverses the state of the operand. When a condition is true,
then the Logical NOT operator will make it false and vice-versa.
Ex: (!a) is false. |

**Bitwise Operators**

Here is the complete set of JavaScript bitwise operators:

(Let’s assume variable a=2 and b=3)

Sr
No | Operators
and Description |
---|---|

1 | & (Bitwise AND) It performs Boolean AND operation on each bit of the
variable placed after it.
Ex: (a&b) is 2. |

2 | | (BitWise OR) It performs Boolean OR operation on each bit of the
integer.
Ex: (a | b) is 3. |

3 | ^ (Bitwise XOR) It performs Boolean exclusive OR operation on each bit
of the integer. XOR means either of the operands is true, but not both.
Ex: (a^b) is 1. |

4 | ~ (Bitwise Not) This unary operator operates by reversing all the bits
of the operand.
Ex: (~b) is -4 here. |

5 | << (Left Shift) It moves all the bits in its first operand to the left
by the number of places specified in the right side expression/operand. New
bits are filled with zeroes. Shifting a value left by one position is
equivalent to multiplying it by 2.
Ex: (a << 1) is 4. |

6 | >> (Right Shift) The left operand’s value is shifted to the right by the
number of bits specified by the right operand/expression.
Ex: (a >> 1) is 1. |

7 | >>> (Right shift with Zero) It’s same as the >> operator, except that the bits
shifted in on the left are always zero.
Ex: (a >>> 1) is 1. |

**Assignment Operators**

Here is the complete set of JavaScript assignment operators:

Sr No | Operators and Description |
---|---|

1 | = (Simple
Assignment) It assigns values from the right side
operand/expression to the left side operand
Ex: c= a + b assigns the value of
(a+b) into c |

2 | += (Add and
Assignment) It adds the right operand/expression
to the left operand and assigns the final result to the left operand.
Ex: c+= a is same as c = c + a |

3 | −= (Subtract and
Assignment) It subtracts the right
operand/expression from the left operand and assigns the final result to the
left operand.
Ex: c-= a is same as c=c – a |

4 | *= (Multiply and
Assignment) It multiplies the right
operand/expression with the left operand and assigns the final result to the
left operand.
Ex: c*=a is same as c = c*a |

5 | /= (Divide and
Assignment) It divides the left operand with the
right operand/expression and assigns the final result to the left operand.
Ex: c /=a is same as c = c/a |

6 | %= (Modules and
Assignment) It takes modulus using two
operands/expressions and assigns the final result to the left operand.
Ex: c %= a is same as c=c % a |

Note: Same logic applies to Bitwise operators also. They’ll become <<=, >>=, >>=, &=, |=, ^=.

**Conditional Operator(? : )**

It is short form of an if-else statement. This operator first checks whether an expression is true or false and then executes one of the two given statements depending upon the result of the evaluated condition i.e., true or false.

Sr No | Description |
---|---|

1 | ? : (Conditional) Is condition true? Then value is a :
otherwise value becomes b |

**Special Operators**

The unary type operator typeof operator is placed just before its single operand, which can be of any datatype.

It determines the datatype of its argument. It returns string. Here is the complete list of the return values for the typeof Operator:

Sr No | Type | String Returned by typeof |
---|---|---|

1 | Number | number |

2 | String | string |

3 | Boolean | boolean |

4 | Object | object |

5 | Function | function |

6 | Undefined | undefined |

7 | Null | object |