Categories of Types & Variables

There are 2 categories of types:
	Primitive Types
		- Built into the language
		- Always start with a lowercase letter
		- The only primitive types are
			- byte (-128 to 127)
			- short (-32,768 to 32,767)
			- int (-2b to 2b)
			- long (-9t to 9t)
			- float (decimal value :: 32 bits)
			- double (decimal value :: 64 bits)
			- char (a single character)
			- boolean (true or false)

	Reference Types
		- Created by developers via classes
		- Should always start with uppercase letter
		- Creating new reference types is extremely common

There are 3 categories of variables:
	Class Variables
		- Belongs to the class, not objects
		- Defined in the class
		- Static
    Instance Variables
		- Belongs to an object
		- Defined inside a class
		- Non-static
	Local Variables
		- Belongs to a method/constructor
		- Can access instance/class variables
		- Cannot be accessed outside of the method