JavaScript Operators

Operators in JavaScript with examples:

Operator Type	Operator	Description	Example	Result
Arithmetic	+	Addition	5 + 3	8
	–	Subtraction	5 – 3	2
	*	Multiplication	5 * 3	15
	/	Division	6 / 3	2
	%	Remainder (modulus)	5 % 2	1
	**	Exponentiation	2 ** 3	8
Assignment	=	Assignment	x = 5	x is 5
	+=	Addition assignment	x += 3	x = x + 3
	-=	Subtraction assignment	x -= 2	x = x – 2
	*=	Multiplication assignment	x *= 2	x = x * 2
	/=	Division assignment	x /= 2	x = x / 2
	%=	Remainder assignment	x %= 2	x = x % 2
	**=	Exponentiation assignment	x **= 2	x = x ** 2
Comparison	==	Equal to	5 == ‘5’	true
	===	Strict equal to (value and type)	5 === ‘5’	false
	!=	Not equal to	5 != ‘5’	false
	!==	Strict not equal to	5 !== ‘5’	true
	>	Greater than	5 > 3	true
	<	Less than	5 < 3	false
	>=	Greater than or equal to	5 >= 5	true
	<=	Less than or equal to	5 <= 3	false
Logical	&&	Logical AND	true && false	false
	||	Logical OR	true || false	true
	!	Logical NOT	!true	false
Bitwise	&	Bitwise AND	5 & 1	1 (0101 & 0001)
	|	Bitwise OR	5 | 1	5 (0101 | 0001)
	^	Bitwise XOR	5 ^ 1	4 (0101 ^ 0001)
	~	Bitwise NOT	~5	-6 (bitwise NOT of 0101)
	<<	Bitwise left shift	5 << 1	10 (0101 << 1)
	>>	Bitwise right shift	5 >> 1	2 (0101 >> 1)
	>>>	Bitwise unsigned right shift	5 >>> 1	2
Ternary	? :	Ternary (conditional) operator	true ? ‘yes’ : ‘no’	‘yes’
Type	Typeof	Returns the type of a variable	typeof 42	“number”
	instanceof	Checks if an object is an instance of a class	obj instanceof Array	true if obj is an array

Operator precedence

Here’s a comprehensive table that classifies JavaScript operators, provides examples, and includes their precedence and associativity:

Precedence	Operator	Description	Example	Result		Associativity
1	()	Grouping	(1 + 2) * 3	9		n/a
2	new (with argument list)	Object Creation	new Date()	Creates a new Date object		n/a
3	.	Member Access	obj.property	Accesses property  of obj	Left-to-right
	[]	Computed Member Access	arr[0]	Accesses first element		Left-to-right
4	new (without argument list)	Object Creation	new Object	Creates a new Object		Right-to-left
5	++	Postfix Increment	x++	x, then x + 1		n/a
	--	Postfix Decrement	x--	x, then x - 1		n/a
6	++	Prefix Increment	++x	x + 1, then x		Right-to-left
	--	Prefix Decrement	--x	x - 1, then x		Right-to-left
	+	Unary Plus	+x	Converts x to a number		Right-to-left
	-	Unary Negation	-x	Negates x		Right-to-left
	~	Bitwise NOT	~x	Inverts bits of x		Right-to-left
	!	Logical NOT	!x	Inverts x‘s truthiness		Right-to-left
	typeof	Type of	typeof x	Returns type of x		Right-to-left
	void	Discards return value	void x	Evaluates x without returning		Right-to-left
	delete	Deletes property	delete obj.property	Deletes property of obj		Right-to-left
7	**	Exponentiation	2 ** 3	8		Right-to-left
8	*	Multiplication	2 * 3	6		Left-to-right
	/	Division	6 / 3	2		Left-to-right
	%	Remainder	5 % 2	1		Left-to-right
9	+	Addition	1 + 2	3		Left-to-right
	-	Subtraction	5 - 2	3		Left-to-right
10	<<	Bitwise Left Shift	5 << 1	10		Left-to-right
	>>	Bitwise Right Shift	5 >> 1	2		Left-to-right
	>>>	Bitwise Unsigned Right Shift	5 >>> 1	2		Left-to-right
11	<	Less Than	5 < 3	false		Left-to-right
	<=	Less Than or Equal To	5 <= 3	false		Left-to-right
	>	Greater Than	5 > 3	true		Left-to-right
	>=	Greater Than or Equal To	5 >= 3	true		Left-to-right
	in	Property in Object	'x' in obj	true if obj has x		Left-to-right
	instanceof	Instance of Object	obj instanceof Array	true if obj is an Array		Left-to-right
12	==	Equal	5 == '5'	true		Left-to-right
	!=	Not Equal	5 != '5'	false		Left-to-right
	===	Strict Equal	5 === '5'	false		Left-to-right
	!==	Strict Not Equal	5 !== '5'	true		Left-to-right
13	&	Bitwise AND	5 & 1	1		Left-to-right
14	^	Bitwise XOR	5 ^ 1	4		Left-to-right
15	`	`	Bitwise OR	`5		1`
16	&&	Logical AND	true && false	false		Left-to-right
17	`		`	Logical OR		`true
18	??	Nullish Coalescing	null ?? 'default'	'default'		Left-to-right
19	? :	Conditional (Ternary)	true ? 'yes' : 'no'	'yes'		Right-to-left
20	=	Assignment	x = 5	x is 5		Right-to-left
	+=	Addition Assignment	x += 3	x = x + 3		Right-to-left
	-=	Subtraction Assignment	x -= 2	x = x - 2		Right-to-left
	*=	Multiplication Assignment	x *= 2	x = x * 2		Right-to-left
	/=	Division Assignment	x /= 2	x = x / 2		Right-to-left
	%=	Remainder Assignment	x %= 2	x = x % 2		Right-to-left
	**=	Exponentiation Assignment	x **= 2	x = x ** 2		Right-to-left
	<<=	Left Shift Assignment	x <<= 1	x = x << 1		Right-to-left
	>>=	Right Shift Assignment	x >>= 1	x = x >> 1		Right-to-left
	>>>=	Unsigned Right Shift Assignment	x >>>= 1	x = x >>> 1		Right-to-left
	&=	Bitwise AND Assignment	x &= 1	x = x & 1		Right-to-left
	^=	Bitwise XOR Assignment	x ^= 1	x = x ^ 1		Right-to-left
	`	=`	Bitwise OR Assignment	`x		= 1`
21	,	Comma	x = 1, y = 2	y is 2		Left-to-right

• Associativity defines the order in which operators of the same precedence are processed.
  Left-to-right means they are processed from left to right, and right-to-left means they are processed from right to left.

Let’s illustrate operator precedence with an example that combines several types of operators.

Example:

let result = 5 + 3 * 2 ** 2 - (6 / 3) && 4 || false;

Let’s break down this
expression step by step according to operator precedence:

1.    Grouping (()):

1. • Evaluate (6 / 3) first because of parentheses.
   • Result: 2

2.    Exponentiation (**):

2. • Evaluate 2 ** 2 next.
   • Result: 4

3.    Multiplication (*):

3. • Evaluate 3 * 4 next.
   • Result: 12

4.    Addition and Subtraction (+, -):

4. • Evaluate 5 + 12 next.
   • Result: 17
   • Then evaluate 17 - 2.
   • Result: 15

5.    Logical AND (&&):

5. • Evaluate 15 && 4.
   • Result: 4 (since 15
     is truthy, the result is 4)

6.    Logical OR (||):

6. • Evaluate 4 || false.
   • Result: 4 (since 4
     is truthy, the result is 4)

So, the final result of the expression let result = 5 + 3 * 2 ** 2 - (6 / 3) && 4 || false; is 4.