Operators In JavaScript
● Operators are used to perform operations on values and variables.
Before learning about Operators, It’s important to understand how Quotes work in JS.
We have three types of quotes to write strings:
• " " (Double quotation) - For String
• ' ' (Single quotation) - For String
• ` ` (Backticks) - For String and JSX
Let’s say you want to print this kind of text in console.
Hello my name is "Urvish"
You might try this
console.log("Hello my name is "Urvish""); // ❌ Uncaught SyntaxError
❌But it doesn’t work — because the inner double quotes confuse JavaScript.
It thinks the string ends early.
✔️We can fix it in two ways:
1. Use backticks or single quotes outside:
We can wrap whole string in to another quotation instead of that one which exist in string.
console.log(`Hello my name is "Urvish"`); // ✅ Wrap Whole in ` `
console.log('Hello my name is "Urvish"'); // ✅ Wrap whole in ' '
2. Use backslash \ to escape double quotes:
Backslash Helps to consider " " as a string in js.
console.log("Hello my name is \"Urvish\""); // ✅
Used to perform mathematical calculations:
We can Craft & Calculate any kind of formula using this operators.
let a = 10, b = 3;
let sum = a + b;
console.log("Sum: ", sum); // 13
let sub = a - b;
console.log("Sub: ", sub); // 7
let mul = a * b;
console.log("Mul: ", mul); // 30
let div = a / b;
console.log("Div: ", div ); // 3.333...
let mod = a % b;
console.log("Mod: ", mod); // 1 (remainder)
let pwr = a ** b;
console.log("Pwr: ", pwr); // 1000 (a to the power b)
a++; // Increment
console.log("Increment: ",a); // 11
b--; // Decrement
console.log("Decrement: ",b); // 2
Sum: 13
Sub: 7
Mul: 30
Div: 3.3333333333333335
Mod: 1
Pwr: 1000
Increment: 11
Decrement: 2
Used to assign and update values:
This is the simple and short way to assign and update value in itself without using another variable.
let x = 5;
console.log("x is " , x);
x += 3;
console.log( "x += 3 :", x ); // x = x + 3 → 8
x -= 2;
console.log( "x -= 2 :", x ); // x = x - 2 → 6
x *= 2;
console.log( "x *= 2 :", x ); // x = x * 2 → 12
x /= 4;
console.log( "x /= 4 :", x ); // x = x / 4 → 3
x %= 2;
console.log( "x %= 2 :", x ); // x = x % 2 → 1
console.log("x is ", x); // 1
x is 5
x += 3 : 8
x -= 2 : 6
x *= 2 : 12
x /= 4 : 3
x %= 2 : 1
x is 1
Used to compare values:
Also this can be Used as a conditional Statements in Logical Decisions.
console.log( 5 == "5" ); // true (values match)
console.log( 5 === "5" ); // false (types differ)
console.log( 5 != "5" ) ; // false
console.log( 5 !== "5" ); // true
console.log( 7 > 5 ); // true
console.log( 7 < 5 ); // false
console.log( 5 >= 5 ); // true
console.log( 4 <= 3 ); // false
true // 5 == "5"
false // 5 === "5"
false // 5 != "5"
true // 5 !== "5"
true // 7 > 5
false // 7 < 5
true // 5 >= 5
false // 4 <= 3
// The condition is 10 > 5
if(10 > 5){
console.log("Ten is greater than five");
}
// The condition is 5 > 10
if(5 > 10){
console.log("5 is more than 10."); // if condition is True
}else{
console.log("5 is not more than 10."); // if condition is false
}
Ten is greater than five
5 is not more than 10.
Used with booleans or conditions:
console.log(true); // true
console.log(false); // false
console.log(true && true); // true (AND)
console.log(true && false); // false (AND)
console.log(false && false); // false (AND)
console.log(true || true); // true (OR)
console.log(true || false); // true (OR)
console.log(false || false); // false (OR)
console.log(!true); // false (NOT)
console.log(!false); // true (NOT)
true
false
true // true and true = true
false // true and false = false
false // false and false = false
true // true or true = true
true // true or false = true
false // false or false = false
false // Not true
true // Not false
Shorthand for if...else:
Used for deciding Statement from condition too quickly.
let age = 20;
let result = (age >= 18) ? "Adult" : "Minor";
console.log(result); // "Adult"
Adult
This Operators are used for Binary operations.
Let's consider 5 and 1.
• 5 = 0101 (4-bit in binary)
• 1 = 0001
console.log(5 & 1); // 1 (binary AND)
console.log(5 | 1); // 5 (binary OR)
console.log(5 ^ 1); // 4 (XOR)
console.log(~5); // -6 (NOT)
console.log(5 << 1); // 10 (shift left)
console.log(5 >> 1); // 2 (shift right)
Rule: Only 1 & 1 gives 1, everything else is 0.
0101 (5)
& 0001 (1)
= 0001 → 1
1
Rule: If either bit is 1, result is 1.
0101 (5)
| 0001 (1)
= 0101 → 5
5
Rule: Result is 1 only if bits are different.
0101 (5)
^ 0001 (1)
= 0100 → 4
4
Rule: Flips every bit: 1 becomes 0, and 0 becomes 1.
For 32-bit integers:
00000000 00000000 00000000 00000101 (5)
~ 11111111 11111111 11111111 11111010 (-6)
-6
Rule: Shifts bits to the left by 1, adds a 0 at the end (×2 each shift).
0101 (5)
<< 1
= 1010 → 10
10
Rule: Shifts bits to the right by 1 (÷2 each shift).
0101 (5)
>> 1
= 0010 → 2
2
In some case we used + and , in console.log(); or any other way to print output.
This can be little mistake if you can't use properly.
console.log("Sum: " + 5 + 6);
Sum: 56
Due to JavaScript's automatic type conversion,
It start adding into String because we do Concatinating using +.
Also we can get many other bugs if we dont take care of it.
To avoid such this kind of Bugs and Errors. prefer to use , (Semicolon).
console.log("Sum: " , 5 + 6);
Sum: 11