## DEV Community is a community of 620,905 amazing developers

We're a place where coders share, stay up-to-date and grow their careers. # Negative zero in JavaScript

Seriously? This topic! Yes. JavaScript actually has two different representations for ZERO:

• Positive zero, represented by +0 / 0
• Negative zero, represented by -0

This is because JavaScript implements the IEEE Standard for Floating-Point Arithmetic (IEEE 754),
which has signed zeroes.

And on a note, both zeroes are equal to one another.

``````+0 === -0 // true
+0 == -0 // true
``````

The only difference between both is in dealing with Infinity

``````1 / +0 // Infinity
1 / -0 // -Infinity
-1 / +0 // -Infinity
-1 / -0 // Infinity
``````

Numbers always need to be encoded to be stored digitally. But why do some encodings have two Zeros?

Let us look at encoding an integer as a 4-digit binary number by the sign-and-magnitude method.

Here,

• One bit denotes the sign. (0 if positive, 1 if negative)
• Remaining bits for the magnitude. (absolute value)

Therefore, -2 and +2 are encoded as,

1 | 0 | 1 | 0 | => -2

0 | 0 | 1 | 0 | => 2

Which means, we will also have two zeroes!

``````1000 // -0
000 // +0
``````

### Hunt 🤔

We saw that -0 and 0 are equal.
Imagine, you came across a use case to return false while comparing -0 and 0.

How would you do that??? (Comment below)

😎Thanks for Reading | Happy Coding⚡

## Discussion (2) 