suresh What is the difference between null and undefined in JavaScript?
When it comes to JavaScript, understanding the distinction between null and undefined is crucial for writing efficient code. The focus keyword "null and undefined in JavaScript" delves into this very topic.
Undefined: In JavaScript, a variable is considered undefined when it has been declared but has not been assigned a value. It is essentially a placeholder that signifies the absence of a value.
Null: On the other hand, null is a specific value that represents the absence of any object value. It is explicitly assigned to a variable by the developer.
It's important to note that while null is a deliberate assignment, undefined typically occurs when a variable has not yet been assigned a value or when accessing an object property that does not exist.
In summary, the key distinction between null and undefined in JavaScript lies in their origins and intended uses within the language. By recognizing and appropriately handling these differences, developers can write more robust and error-free code.
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