What does != mean in js?

!= operator represents inequality in JavaScript and is used to compare whether the values ​​of two expressions are not equal. Its usage is: expression1 != expression2. Returns true if the expressions are not equal and false if they are equal. It contrasts with == (loose equality) and === (strict equality). != does not automatically perform a type conversion when comparing numbers (e.g. 1 != '1' returns true). It can compare any data type. To perform a strict inequality comparison, use the !== operator.

!= Meaning in JavaScript

In JavaScript, the != operator means not equal, similar to != or <> operators in other programming languages. It is used to compare two values ​​if they are not equal.

Usage and Syntax

The syntax for using the != operator is as follows:

<code>expression1 != expression2</code>

where expression1 and expression2 are the expressions to be compared. If the two expressions are not equal, the result is true; otherwise, it is false.

Examples

Here are some examples of the != operator:

<code>'hello' != 'world' // true
10 != 15 // true
[] != [] // true
null != undefined // false</code>

Differences from == and ===

In JavaScript, there are two equality operators:

• ==: Loose equality operator, convert the value to the same type and then Compare.
• ===: Strict equality operator, no type conversion, direct comparison of values.

Thus, the != operator is the opposite of the == and === operators, expressing both loose and strict inequality.

Note

• != operator does not automatically perform type conversion when comparing numbers. For example, 1 != '1' returns true because JavaScript treats the string '1' as a different value than the number 1.
• != operator can compare any data type, including basic types (numbers, strings, booleans, etc.) and objects.
• If you want to do a strict not-equal comparison, use the !== operator.

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