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Please enable JavaScript in your browser settings or update your browser.Learn Undefined | Data Types and Variables
Introduction to JavaScript
SectionΒ 3. ChapterΒ 31
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What is Undefined

Undefined is also a data type in JavaScript just like the null. When a variable is created or declared without assigning any value to it, then the value of the variable will be set as undefined by default.


              
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let age;
console.log(age);
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Task

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Declare a variable numberOfItems and assign the value of undefined to the variable and show the value of the variable.

Solution

So, undefined variables can also be declared using the undefined keyword.

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SectionΒ 3. ChapterΒ 31
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