In JavaScript, a null value represents the intentional absence of any object value. It is one of the primitive values in JavaScript, along with undefined, boolean, number, string, and symbol. Null is often used to initialize variables that have not yet been assigned a value or to represent the absence of a value in a property or object.
There are several ways to check for null values in JavaScript. One way is to use the strict equality operator (===). The strict equality operator checks for both the value and the type of the operands. If either operand is null, the result of the comparison will be false.