01. Data Types

Depending on who you ask, JavaScript offers between four to six data types. These data types can be broken down into two categories - those that store literal values (simple data types; eg. boolean, number, string), and those that store a reference in memory (reference data types; eg. arrays and objects).

Simple Data Types

The five simple data types we'll be covering include:

  1. Boolean
  2. Number
  3. String
  4. Undefined (no value yet assigned)
  5. Null (no value)

Reference Data Types

Reference data types take up more space in memory, and are referenced by an address. These data types include objects like arrays and functions that you can call. We'lll look at arrays in this section, but since objects are so special, we'll save them for its own section.

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