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The daily developer
The daily developer

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JavaScript Tutorial Series: Operators.

Operators are distinct symbols used to perform operations on operands such as values and variables.

We've seen an operator in the previous post, which is the assignment operator.

Before we start this lessons about operators let's talk about comments.

Comments

Comments are a small description that you can add to your code to make it readable. Comments are also used to stop the execution of a line of code since the compiler parses and then discards comments.

There are two types of comments:

  • single-line comment
// this is a comment
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  • multi-line comment
/* this comment can 
span across 
multiple lines*/
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Assignment operator

You assign a value to a variable using the assignment operator.

let age = 25;
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In the example above we've assigned 25 to the variable age.

Arithmetic operators

operator description
+ addition operator
- subtraction operator
* multiplication operator
/ division operator
% remainder operator
** Exponentiation operator
++ increment operator
-- decrement operator

Here are some examples:

let x = 3;
x = x + 7  //10 

let y = 10;
y = y / 2; //5
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A shorthand can be used to do these operation:
This works the same with subtraction multiplication and division

Using the example above

let x = 3;
x = x + 7  //10 

//instead of writing x = x + 7;
x += 7; //10 
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Increment and Decrement

Increment

The increment operator increases the value of a variable by 1.

let x = 1; 
x++;
console.log(x); //2
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Decrement

The decrement operator decreases the value of a variable by 1.

let y = 1; 
y--;
console.log(y); //0
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Prefix and postfix increment and decrement

Prefix

Prefix increment/decrement first increases or decreases the value then executes the statement.

Postfix

Postfix increment/decrement executes the statement then increases or decreases the value.

Exponentiation

Using this operator raises the first operand to the second operand's power.

let x = 5;
let y = 3;

let result = x ** y;
console.log(result); //125
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Remainder operator

The remainder operator returns the remaining part of a division/

let x = 7 
let y = 3 
let result = x % y;
console.log(result); //1
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Top comments (2)

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mizouzie profile image
Sam

I never knew you could prefix OR postfix ++/--

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fullstackjo profile image
The daily developer

yes that is because postfix is more used than prefix