Data Types

Values in JavaScript can have numerous different types, known as Data Types. Data types can be described as either primitive or object (don't worry about this too much), where the primary key data types are as follows:

• Primitive
• • Number represents all numerical values, including integers, decimals, and exponents. (e.g., 10, 3.14, 1e5).
  • String represents sequences of characters enclosed in quotes. (e.g., "Hello", 'World!', "").
  • Boolean represents truth values, either true or false. (e.g., true, false).
  • Null represents the absence of a value. It's different from undefined. (e.g., null).
  • Undefined represents the absence of a value due to not being assigned yet or a reference pointing to nowhere. (e.g., undefined).
• Object
• • Object (or dictionary) is a complex data type that allows you to store collections of key-value pairs. Example: { name: 'John', age: 30 }.
  • Array (or list) is a special type of object used to store ordered collections of values. Example: [1, 2, 3, 4].
  • Function is a subtype of object that can be invoked/called. Example: function add(x, y) { return x + y; }.

When assigning values to a variable, it's important to ensure that the value is both a viable data type, and the correct data type.