QUESTION 7 OF 30

Please discuss the difference between null, undefined or undeclared variables.

Another technical question asking you to discuss the differences between several terms or concepts used in this profession. To prepare for an interview, you should research the company, the products it produces, and the type of programming you're likely to encounter. You can find information about this on the company's website and in the job description. Once you understand this, you should be prepared to answer questions related to the work they do. Any answer you provide to a question should be within the context of this.

"Null, undefined, and undeclared are different types and states of variables used within the JavaScript programming language. Null is a value of a variable, which is a type of object. A variable is considered undefined when declared, but no value has been assigned to it. An undeclared variable occurs when the code tries to access the variable, and it has not been initialized or declared earlier using a var or const keyword."

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Anonymous Answer

Null is an actual value that's an object that you can assign to a variable.

Undefined means no value has been assigned to a variable but it has been declared.

Undeclared means the name of the variable hasn't even been defined yet using let, var, or const.

The first two will result in a false check-in of statements and the last will give a runtime error.

Amanda's Feedback

Well done! You've clearly explained each and what the results of each would be.

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Please discuss the difference between null, undefined or undeclared variables.

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