In this fourth part of the Javascript for Beginners series, I will be covering over Undefined and Null data types, including their similarities and differences. Undefined and Null can be seen as interchangeable most of the time even though they are not exactly the same technically speaking. At their core, they represent different values, but are generally the same kind of data type. This leads me into another important concept in Javascript called type coercion, or automatic type conversion. Type coercion is designed into the Javascript language being that it is a loosely typed programming language and allows for this level of flexibility. Whereas other languages that are strongly typed or static require variables and values to be assigned a data type identification. The list of examples in this tutorial can be viewed directly in the Github link below:

Github Link to Undefined.js file:

Typeof operator MDN documentation:


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